The smoke was real.

I knew it before the cabin voice had finished reminding Freight to remain seated. The core could fake an orange fireball in a vacuum, and the shudder of a drive plate tearing loose, and eggs. It could not fake the inside of Lalu's flat.

The black plume curling through the louvres behind the recliner tasted of ground cardamom from Maddy's kettle, burnt rosin from the workbench, and a sharp, coppery vinegar bite I had smelled once before, during a Riot and Compliance drill in Sub-Basement Two. Linguafranca® corridor smoke. That was the metal thing I had heard hit the floorboards and roll. Somebody on the Tier 64 landing had slipped a dispersal canister under Lalu's iron-barred door, and our three bodies, strapped into his uncle's rig in a room I couldn't see, were breathing it in.

Under the painted coffee ring, the red counter ticked from 04:05 to 04:04.

"Lalu," I said, coughing into my wrist. "That isn't the ship. That's your hallway."

He didn't answer. He lay almost flat in the recliner with the two amber suns steady in his glasses, smiling at the asteroid as if it had just said something kind.

"Lalu!"

I leaned across the aisle and hit the VIEW TUNER panel with the flat of my hand. TIDE clicked off.

For a second nothing happened. Then the amber went out of his lenses, the recliner banged upright like a lift arriving at its floor, and Lalu blinked at me, at the smoke, at the alarm lights wheeling round the deck.

"Who said you could touch my dials?" he said. "Oh, bloody hell. Is that my kitchen?"

It was his own voice, joke and all. Until that moment I hadn't known how afraid I had been of never hearing it again.

He seized the manual flight yoke that had risen out of the deck between his knees and hauled back on it. Outside the forward viewport, the jagged bulk of Delta-9 spun across the stars like a server rack tumbling down an empty lift shaft. The derelict plate had torn the starboard thruster cowl clean off its mounts. Every time Lalu fired the port jets to nose us toward open space, the kilometre-long rock dragged the bow back down toward its broken smelting towers.

In my left ear, under the roar of the virtual thrusters, a dry, static-choked voice came across the copper induction band from the flat, like somebody shouting up a rainpipe from three floors down.

"Lalu!" It was Maddy, and behind her came the muffled thump of something heavy striking a door. "You've got company on the landing, pal. Four Linguafranca® custody jackets, a thermal lance and two smoke pots. The bars on the doorframe are holding, and your vent's pulling most of the gas up the pylon shaft. What's your status?"

"Tell them to take a number!" Lalu shouted, his knuckles white on the yoke as a ruptured oxygen gantry whipped past our belly. "Pull us out, Maddy! Cut the transformer!"

"No can do, honey. When you slotted that cylinder, the old flight core locked the neural relay until the incident tape finishes its readout. Yank your plugs while it's running and the three of you spend the rest of the week reading with your fingers. Ride it out from the inside. They'll be through the lower hinge about the time your counter hits zero."

The side-band clicked shut in a wash of static.

I was already reaching across for the wire-guarded red handle under the right armrest of the recliner, the one that was supposed to wake us up staring at Lalu's sink.

Lalu caught my wrist so hard it hurt. "Not that one. Not with the tape running."

"You said it was the way out."

"It's a way out," Lalu said, and he didn't let go until I had taken my hand back. "It isn't the one you want."

In the observer's seat, Sethu gripped his brass grab-rail with his hair plastered to his forehead and his olive coat twisted under the straps. He coughed into his sleeve and frowned at the green trajectory rings tightening on his glass.

"I said a kilometre of iron," he said. "I was wrong. A kilometre of iron couldn't hold a dropped spoon, let alone a ship. Why is it pulling like a planet?"

"It's not the rock, Professor. It's the core." Lalu kicked the rudder pedals hard left as a string of frozen cargo containers tumbled past the glass. "When the Consortium mined platinum out here, they sank a gravimetric mass-anchor down the central shaft so the smelting crews could walk about in boots. Nobody ever switched it off. With the starboard drive gone, we can't climb straight out of the well."

On the central scope, a white dotted line wrapped round the kidney-shaped rock like cable round a drum, passing over the blown airlocks and rising back toward the debris ring every twenty seconds.

"Slingshot round the tail?" I said.

"With one thruster bank? We'd pancake into Smelter Tower Three on the second turn. Look at the bottom of your screen."

Along the lower rim of the glass, beside the red counter ticking through 03:48, a row of thirty blue capacitor bars had begun to fill from left to right at a maddeningly sedate pace:

AUXILIARY HYPERDRIVE PRE-CHARGE: ORBIT 02 OF 30 BLACK-BOX TELEMETRY UNLOCK: SECTOR RING 1 (04.19.81)

"The auxiliary hyperdrive draws off the gravity coils every time we cross the rock's magnetic poles," Lalu said, wiping the sweat off his jaw. "Thirty times round gives us enough charge to punch out of the well. It also finishes the cylinder's readout, so the chair lets us go."

The rusted ribcage of the dead colony swung up over the nose for the third time in a minute, and the three tethered helmets outside Airlock Four glinted in the distant sun.

"Thirty orbits," I said. "So now we're going in circles on purpose."

"Because of a revolution on Delta-Nine," Lalu said, and in spite of the smoke in his throat and the men with a lance outside his door, he let out a short, barking laugh. "Appreciate the symmetry, Sarkowski. My uncle loved a bad pun."

On the fourth pass, the green archive receiver locked onto the colony's wide-band mast. Across our cabin glass, over the orange letters on the hull below, a grainy recording from April 19, 2181, began to play. In a rock tunnel lit by swinging work-lamps, hundreds of miners in grey coveralls were hammering drill-bits against the steel air ducts under a banner torn from a cargo tarpaulin:

NO MASTER // NO LEDGER // EVERY MAN HIS OWN LAW

A young man with grease on his cheekbones stood on an overturned ore cart.

"They tell you the contract is sacred!" he shouted, and the tunnel roared back at him. "They tell you the law is the beam that holds up the roof! Look up, brothers! The only thing holding up that rock is your own shoulders! Every statute on their ledger is a leech on your neck, so a clerk in a clean shirt eighty million kilometres away can call himself righteous!"

"Listen to the cadence," Sethu murmured. "He isn't asking for rations. He's preaching."

The young man raised a plasma torch, its blue pilot flame hissing above the crowd.

"A man who obeys a law he didn't write with his own hand is cattle! Tonight we smash the clocks, we burn the ledgers, and we build the first free city in the belt. A society without obedience! A unity in disobedience! Every man his own master, every man his own author, every man a god!"

Something hot stirred under my ribs as I watched him. For five years I had sat on the eighty-fourth floor of Globank Tower watching Vane turn compliance statutes into weapons, watching the chairman turn men into balance sheets with a gold pin, watching Wheatley dim my lights for my own good. Part of me wanted a spanner and the nearest clock.

Then the ship swung out of the asteroid's shadow on Orbit Seven, and the tunnel we had just been watching passed beneath the viewport.

Its steel doors had been blown outward from within. Frozen in the spilled slag round the threshold lay two dozen men in grey coveralls, cut down from behind at ranges so close that their suits had fused to the rock. Beside the frame, somebody had painted a second slogan over the first, in dark brown, before the air ran out:

COMPLIANCE BY ORDER OF FREE COMMITTEE THREE // TRAITORS TO LIBERTY WILL BE AIRLOCKED

The heat in my chest turned to ice water.

"Free Committee Three lasted about ninety minutes, by the timestamp," Lalu said quietly. "Until Free Committee Four decided Three wasn't disobedient enough and blew the main seal."

"A unity in disobedience," I said. "Every man a god. So what happens five minutes after the revolution, when two gods want the same oxygen tank?"

"They take a vote," Lalu said, without any heart in it.

"And why would a god obey a vote he lost?" Sethu asked, looking down at the men in the slag.

Nobody answered him. The answer was lying outside the door in two dozen grey coveralls.

I thought of the chairman, who recognized no law above his ledger, and of the boy on the cart, who had recognized none above himself. They were two points on the same orbit.

As the Starship dropped into the steep bottom turn of Orbit Nine, the floor fell out from under my stomach while the smoke in Lalu's flat bit into my lungs. My fingers slipped off the console, the buckle of my harness clicked open under my elbow, and I pitched forward onto my knees on the deck plates, coughing until black spots swam across the stars.

"Easy, buddy. I've got your collar."

Two hands caught me under the arms and hauled me back into the navigator's seat. Lalu had locked the yoke on its gimbal for five seconds and was leaning half out of his recliner, while Sethu pulled my straps tight and snapped the latch home across my chest.

"Breathe through your sleeve," Sethu said, pressing a clean corner of his linen cuff into my left hand. "Shallow breaths. The vent in the flat is clearing the worst of it. You're fighting two sets of inner ears at once."

On the flight deck, my right hand lay on the armrest. In the flat, I made it find the pipe. Cold iron, and the blister near the valve. I held on.

Under the coffee ring, the red counter said 03:02. Above it: ORBIT 10 OF 30 // AUXILIARY CHARGE: 33%. The broken smelting towers wheeled past for the tenth time, chased by the three crooked stars.

"We're never getting off this rock, are we?" I said hoarsely. "Even if your door holds. We go down one pylon and up another, and it's the same loop underneath. Somebody tears the house down in the name of freedom, or somebody welds the windows shut in the name of order. Where does a man put his feet that doesn't spin?"

Behind his dark glasses, Lalu's eyes were quiet and unexpectedly gentle, the way they had been two years ago when I had knelt on his rug holding the same pipe.

"You're looking for the floor in the wrong place, bro."

He reached down to a brass plate beside his right knee, below the VIEW TUNER panel, where a bevelled crystal knob sat recessed in a ring of ivory markings labelled CABIN HARMONICS // INNER VEIL.

"The smart miners out here didn't pick up a torch, and they didn't apply to the compliance office," he said. "My uncle put a second layer in the cushion, for when the outside gets too loud. Listen."

He turned the crystal one click.

The two-tone shriek of the alarm dissolved. In its place, rising through the leather ribs of our seats like warm water filling a bath, came the opening of an old symphony: four string parts entering one after another, weaving a calm golden ceiling over the flight deck. At the same moment the towers and the frozen men outside lost their edges and softened into curtains of pale silver mist, drifting past the bow like steam off a vent stack on a cold morning.

My shoulders dropped an inch before I could tell them not to.

"Turned down the glare," Lalu said, leaning back. "A minute ago the glass showed you rusted iron. Now I turn a crystal ten degrees and it shows you mist. Space, time, Globank, Delta-Nine, those four monkeys with a lance outside my door: it's all a veil of pictures on the inside of your head. And behind the veil, there are two of you."

He held up two fingers in the silver light.

"There's the everyday myself. Sarkowski, vice-president, burnt throat, bricked phone at the bottom of a sump, a chairman who wants a nine on his certificate by six o'clock. He gets scared and goes round in gravity loops. And behind the curtain sits the True-Self. No wallet number. Outside space and time, quiet as the bottom of the sea. Down there, you and me and Sethu and the chairman aren't separate islands knocking into each other. It's one ocean. Nothing is born and nothing dies. You just let go of the little myself that's making all the fuss, and rest."

For five seconds, while the violins climbed and the mist curled past the glass, I understood why the programmers of Sector Seven had once paid Lalu's uncle a month's wages to sit in this chair. When the room is filling with smoke, being told that the fire is a picture on a curtain is the sweetest thing anybody can say to you.

Across the console, Sethu sat upright with his hands folded over his belt buckle, watching the mist with the polite attention he had given Finsics's ninety-per-cent certificate that morning.

"I've got a detective's question," I said. "If my True-Self is already all-powerful and sitting outside time in perfect peace, how did the poor idiot get himself locked inside me?"

Lalu opened his mouth, and paused with one finger in the air.

"Chain of custody," I said. "When an account gets hijacked, there's always an attacker. In your story there's nobody else in the building. So the True-Self woke up one morning, spun a veil full of mining massacres and compliance audits, and locked a piece of itself inside a vice-president, just so he could spend his whole life trying to forget he exists."

"It's a game, bro. The One playing hide-and-seek with itself."

"Tell that to the three helmets outside Airlock Four. And look at the exit clause. Drop a lump of salt in the sea, Lalu, and the sea stays wet, but the salt is gone. If the part of me that remembers my father's paperweight, and knows your laugh, gets wiped at the door, then I haven't been saved. I've been erased, so the ocean can go back to sleep."

"To cure the headache," Sethu said mildly, "the physician removes the head and congratulates the torso on its serenity."

Lalu sighed and drummed his fingers on the panel. "Tough crowd. All right. Nobody gets out on the first pass. You roll the boulder up the hill, it rolls back down, you walk down after it and push it up again, a few million times over. The trick is to smile at the boulder."

Sethu was no longer looking at Lalu. He was looking at the silver mist ahead of the bow, where a darker shape had begun to show through it.

"Lalu," he said. "What's behind your curtain?"

Smelter Tower Three came out of the mist at us like a pylon coming up through the lid.

Lalu slapped the crystal back to zero. The mist snapped away and the iron came back all at once, and so did the alarm, in the middle of its shriek. He threw the yoke over. The tower's broken crown went past the port quartz close enough to show the frost on its rivets, and something along our belly screamed and tore.

A fresh draught of acrid smoke from the Tier 64 corridor caught at my throat, and I coughed until my ribs rattled against the harness latch.

"Look at me, Lalu," I wheezed, when I could. "Do I look like a man smiling at his boulder?"

He looked at my red eyes, my soot-smudged jumper and my white knuckles on the grab-bar, and the solemn mystic mask cracked straight down the middle.

"Okay," Lalu said, grinning. "Maybe you need a bigger boulder."

ORBIT 16 OF 30 // AUXILIARY CHARGE: 53% BLACK-BOX TELEMETRY UNLOCK: CENTRAL SHAFT LAB (04.19.81 // 18:12 UTC)

Under the coffee ring, the red counter ticked past 02:18. On the sixteenth pass, a shattered geodesic dome of reinforced quartz came into view between two slag heaps, and the magnetic pickup in the black cylinder gave a sharp clack as it locked onto the deepest beacon in the rock.

For three seconds there was only the hum of our gravity coils and, far away beneath it, the muffled ring of a crowbar on Lalu's doorframe.

Then a sound came out of the `STARSHIP-09` flight recorder that made all three of us stop breathing.

It was a solo cello, recorded in a small, hard-walled room where you could hear the rosin catch on the horsehair before the note bloomed. It began on one low D, unhurried and dark, and held it for four beats, until a second line entered a fifth above it, not fighting the first note but leaning on it, the way two beams lean together to hold up a roof. A third line stepped in, and a fourth, building a quiet, aching fugue that seemed to climb out of the dead shaft toward the stars.

Nobody spoke until the first phrase came home onto a long, clear chord.

"That isn't the chair," I said. "That's on the Delta-Nine box. Somebody recorded that down in the shaft, the evening the airlocks blew."

Lalu leaned toward the green oscilloscope bars jumping in the corner of his screen. The joke had gone out of his face. He looked like a repairman who had opened a server cabinet and found a violin inside.

"Audio file tied to the lab's neural bus," he said, reading the tags. "Look at the peaks. Two hundred and ninety-three point six hertz, then four-forty, then three-twenty-nine. If it's making the hair on your neck stand up, don't get misty on me. It's pressure waves hitting the little anvil in your ear and dumping a credit's worth of dopamine into your cortex."

Sethu reached across and pressed the HOLD stud. The chord stopped clean, and the quiet that followed seemed to keep its shape.

"How many pressure waves are hitting your ear right now, Lalu?" I asked.

"None. He paused it. While it plays, one crest at a time."

"One at a time," I said. "The note from two seconds ago is gone, and the next one hasn't happened yet. So if your head is meat being tapped by whatever's in the air this instant, why didn't you hear a string of clicks, like rain on a pod roof? How did you hear a tune?"

Lalu opened his mouth, looked at the frozen bars, and closed it again.

Sethu turned the playback dial two notches, up four semitones and twelve per cent faster, and let the HOLD stud go. The fugue came back brighter, at a brisk walk. On the scope, every number had changed. Not one figure matched what Lalu had read out.

"Different tune?" I asked.

"No, same tune, higher and faster," Lalu said, and then winced behind his sunglasses. "Wait."

"Every number on your meter just changed," I said, "and all three of us heard the same tune. So the tune was never the vibrations. They're only the ink and paper it rides on."

Sethu pressed HOLD again. "And notice," he said softly. "The speaker is silent. The air is flat. And you're still humming the last bar, Lalu."

Lalu stopped humming at once and cleared his throat. "Catchy hook, Professor. What's a cello got to do with a mining war?"

I looked at him across the console: the cracked collar turned up, the nose slightly crooked from a university match he still insisted hadn't been rough, the small scar under his chin where he had dropped a soldering iron at nineteen, and behind the absurd indoor sunglasses, the stubborn loyalty that had walked up to Gate Four at half past eight this morning.

"It's like your face," I said.

"First you insult my boulder, now my face? What's wrong with my face?"

"Not a thing." For the first time since Pylon 64, the band round my chest loosened. "Hand your head to Finsics and they'll weigh the water and the carbon, map the bones to four decimal places and log the distance between your ears. Ninety-nine point nine per cent, and they still wouldn't know who walked up to Gate Four this morning to bail me out. A face isn't the sum of the bone, any more than the tune is the sum of the hertz. It's how a person looks out through the flesh."

On the console, the blue bar clicked up to Orbit Twenty.

Lalu didn't make a joke. He looked from me to Sethu, then out through the glass at the three tethered helmets beside Airlock Four, whose visors had been cracked forty years ago so that nobody could see the faces inside.

"All right," he murmured. "There's more to a song than the wire. And there's more to a man than the meat."

Two seconds later he whipped off his sunglasses and stared at us in theatrical horror, one hand clapped to his heart.

"Strike that from the record. Did I just agree with you? Maddy, are you recording on the room bus? It's the smoke! They're pumping compliance gas through my keyhole, I was under duress! Log it as duress!"

"Too late," I said, grinning through the soot. "Sethu's a curator. It's already in the permanent collection."

ORBIT 22 OF 30 // AUXILIARY CHARGE: 73% BLACK-BOX TELEMETRY UNLOCK: PROJECT MASS // CLINICAL & TACTICAL ARCHIVE

Our laughter died ten seconds later, when the red counter hit 01:24 and the twenty-second revolution brought us over the broken dome. The black cylinder opened the file that went with the music. Across the forward glass, replacing the stars, came a split-screen laboratory log stamped in red Consortium capitals:

CONSORTIUM OFF-WORLD DIVISION // DELTA-9 FACILITY PROJECT: M.A.S.S. (MILITARY AUGMENTED SENSORY SUBSTRATE) EXTERNAL AUDIT LOG: INSPECTOR R. V. (SECTOR 7 ENGINEERING)

Lalu went very still in his recliner. His sunglasses stayed in his lap.

"Inspector R. V.," he said. "Those are my uncle's initials. They sent him out here in April eighty-one to audit the telemetry bus before they rolled the chip out to the municipal guard."

On the left half of the screen, a surgical camera watched a wafer of iridescent grey silicon the size of a fingernail being seated at the base of a young security guard's skull. A calm, clipped voice was briefing an unseen board while the cello fugue played softly underneath.

"The bottleneck in off-world extraction has always been sensory hesitation," said the director, as brisk and pleasant as Pemberton pitching a bond issue. "The unaugmented guard suffers an average delay of zero point eight seconds when ordered to discharge a lethal weapon at a striking worker at close quarters. Specifically, fixation on the target's face triggers an involuntary empathy spike."

"He means," Sethu said, very low, "that when a man looks another man in the eye, his conscience tells him not to murder him."

"Project MASS removes the bottleneck at the software layer," the voice went on. "The wafer performs two translations. First, it converts the wearer's emotional brainwaves into structured polyphonic audio, so that supervisors can monitor morale by ear. That is the four-part string recording on Channel One."

My stomach turned over. Nobody had played that cello. It was three hundred men's fear, turned into music in a control booth.

"Second," the voice said, as the right half of the screen switched to a feed through the guard's own eyes, "when the optic nerve detects an unbadged or striking worker within fifteen metres, the wafer intercepts the face before it reaches conscious awareness."

An unarmed miner stepped out from behind an ore cart with both hands raised, shouting something about the water ration. On the wall camera we could see him clearly: a thin man of forty with grey stubble, frightened eyes and grease on his forehead.

Then the screen showed us what the guard saw.

From the neck down, nothing had changed. Above the collar, the face was gone. Where the eyes and the nose and the pleading mouth should have been, the wafer had painted a twitching, faceless oval of glistening grey shell, like the underside of a sewer beetle, and it had scrubbed the words out of his voice and left a wet, rasping hiss.

The guard's pulse readout didn't move. He lifted his plasma cutter and fired into the grey oval.

"By editing five square centimetres of visual data," the director noted, "compliance reached one hundred per cent."

The timestamp jumped six hours to 04.19.81 // 21:04 UTC. An alarm was clanging in the lab, and red text flashed across the log:

WARNING: SMELTER TRANSFORMER SURGE // BADGE WHITELIST SERVER CORRUPTED (16.4% PACKET LOSS) OPTICAL OVERRIDE DEFAULTING TO UNIVERSAL ACTIVE

"Good God," I said.

Sixteen point four per cent. A badge server had dropped a sixth of its packets during the strike, and every wafer in the colony, in the guards and in the miners who had been fitted at their medicals, had stopped recognizing anybody at all. I had spent my whole career inside the margin a number leaves behind. I had never seen what lives there.

The helmet cameras cut across four gallery feeds at once. Every man in the rock looked at his neighbour, his brother, his bunkmate, and saw a hissing grey insect lunging at him in the dark. They were screaming, swinging drills and torches at the monsters crowding the tunnel, while up in the booth the telemetry synth turned the slaughter of three hundred men into a soaring four-part symphony that echoed down the empty shafts until the last airlock blew.

At the bottom of the screen, a final line had been keyed into the cylinder's header in cobalt blue by Inspector R. V., before he pulled the core from the wreck:

CONSORTIUM BOARD RESOLUTION 04.22.81: LOG COLONY LOSS AS METEOR IMPACT. TRANSFER M.A.S.S. OPTICAL-FILTER CODE TO EARTH MUNICIPAL DIVISION (PROJECT LINGUAFRANCA).

For a long time nobody said a word. The only sounds were the thump of the lance on Lalu's door and the click of the capacitor reaching Orbit Twenty-Five.

Sethu was looking at the last two words.

"Your uncle built Inception," he said at last, quite gently. "And then he came out here and audited the eyes they gave Linguafranca®."

"He stole the tape," Lalu said. "He risked his neck to get it out."

"Yes," Sethu said. "And then he locked it in a drawer for forty years."

Lalu's jaw set. For a second I thought one of them was going to say the next thing, and I didn't know which of them I would have to stand beside when he did. Then Lalu looked away at the frozen miner on the screen, and I watched him do what a hardware man does when a machine he understands has done something monstrous: build a firewall between the circuit diagram and the blood on the floor.

"The whitelist glitched," he said, tight and fast. "Cheap single-channel badge server in a high-induction mine, and the surge flipped the bit. Murder by bad engineering. Have the board shot. But if we're talking straight facts, Sarkowski, the chip worked. They didn't argue with the guard's soul. They tweaked fifty milliseconds of traffic between his eye and his trigger finger, and his whole moral world flipped over. Doesn't that prove it? Mercy, fear, music: they're functions of the brain. Input at the eye, a function in the middle, output at the arm."

"Look at that word function," Sethu said quietly. "You're using it the way Vane uses a ledger entry. To hide what's missing."

Lalu's hand had gone to his jacket pocket, the way it always did when he was thinking, and it came out holding the filed brass cage key. The chair had dressed him exactly as he had sat down, right down to the pockets.

"What's the function of that?" I said.

"Opening the cage on Tier Two."

"Now take away the brass, with its teeth filed to a real depth, and take away the hand that turns it. What does the function open?"

"Nothing," Lalu said. "It's just a word."

"A thing has to be something before it can do something," I said. "And when that cello played, did you wait for Maddy to scan your skull and print you a chart before you knew you were moved?"

"Of course not. I felt it."

"From the inside," Sethu said. "A scanner only ever sees the outside of the building. Grey matter, voltage, chemistry, all in the third person. None of it is the I that hears the music." He nodded at the screen, at the grey oval where a man's face had been. "That's why they needed the chip. If a man were only a meat computer, they could have typed a command into the guard's ear. They had to blot out the face, because as long as a man can see a face, the I in him knows the I looking back."

He was quiet for a moment.

"You cannot murder a brother," he said, "until you have paid a machine to tell you he's an insect."

Lalu put the key back in his pocket and said nothing at all.

ORBIT 27 OF 30 // AUXILIARY CHARGE: 90% BLACK-BOX TELEMETRY UNLOCK: SUB-LEVEL VAT ARCHIVE (PROTOTYPE 01)

In the flat on Tier 64, the smell of burnt iron grew suddenly sharper. A shower of real sparks must have come in under the doorframe, because a dry wave of heat brushed my shins while my boots stood on the Starship's deck. Under my right hand, the pipe had begun to tremble.

"They're halfway through the bottom bar, boys!" Maddy's voice came across the band, tight as a stretched cable. "Finish the tape or start praying!"

The twenty-seventh orbit opened the last vault in the cylinder.

It was a white-tiled laboratory below the smelting shafts, lined with glass vats in which bundles of gold-plated optical fibre hung in clear cooling fluid. In the middle of the room stood a brushed-titanium humanoid frame two metres tall, without skin or clothes, its chest open to show a pulsing lattice of synthetic neural gel.

I knew it before the caption finished scrolling. Give it forty years of polished servos and a charcoal suit with a white pocket square, stand it behind the chairman's left shoulder on the eighty-eighth floor, and you had Optimus. The caption said so in one dry line at the bottom: FRAME DESIGN SOLD AT CONSORTIUM LIQUIDATION TO MUSKY INC. (EXECUTIVE CARE DIVISION), 2183.

On the tape, the director stepped up to the frame with a clipboard.

"Having mapped the complete connectome of Subject Fourteen prior to termination," he said, "we have written all eighty-six billion neural weights into the substrate of Prototype One. Observe." He tapped a microphone. "Prototype One. State your feelings regarding your family in Sector Four."

The titanium head turned. Its blue optical ring narrowed by a fraction, and a smooth baritone, without a breath between the syllables, came out of its chest grille.

"I love my wife and child in Sector Four. I would give my life to protect them. I also hold, as a first principle, that a door cannot be locked and unlocked at once."

"All right, beat that!" Lalu shouted over the rising hum of the coils, stabbing a finger at the glass as we banked into Orbit Twenty-Eight. "That's no insect filter, Sarkowski! They copied the man's whole brain map into silicon, every synapse! It remembers his wife! It does logic! In the First Restructuring, old Director Halloran at Globank tried to have his synthetic valet declared his legal son in the Zürich probate court, so his nephew wouldn't get the voting shares! If the wiring's identical down to the last atom, why isn't that a person?"

"How did Zürich rule?" I said, bracing my feet as the deck trembled.

"Threw the toaster out of court and gave the shares to the nephew," Lalu admitted. "Because the judge was on the nephew's payroll! Answer the question!"

"I answered it at Gate Three in BitLocker this afternoon," I said. "This clearance statement is false. Optimus could read that sentence. It went round it in circles until its fan screamed. I just didn't believe it." I pointed at the frame on the screen. "Now listen to what that thing just said. A door can't be locked and unlocked at once. How do you know that, Lalu?"

"Because if it were, the words wouldn't mean anything. You see what both halves mean, and you see they won't fit together."

"You see it. Now how did Prototype One say it?"

"Current through the weights they copied from Fourteen."

"Voltage in at the microphone, down the easiest path through the gel, out at the speaker," I said. "Tonight an engineer swaps two resistors with a pair of tweezers. Tomorrow the same frame stands in the same spot, flashes the same polite blue eye, and says in the same baritone: I hate my wife in Sector Four, and a door can easily be locked and unlocked at once. It won't blush. It won't feel the contradiction. There's nobody home to feel it."

"Because you're looking at one resistor at a time!" Lalu's hands flew across the console as Orbit Twenty-Nine flashed up and the cabin began to hum like a struck tuning fork. "One water molecule isn't wet, bro! One iron atom isn't a magnet! Pack billions of them together in the right pattern and a new property comes out at the top. Why can't a mind come out of eighty-six billion gates?"

"Test it on the bench," I said, fast. "A pinch of iron filings on your workbench. Conscious?"

"No."

"Pack ten billion of them into a ball."

"No."

"Forge them into a neat little cube. Does cubeness give the iron an inner life?"

"No, Sarkowski, it gives you a paperweight!"

"Wire a million cubes together with copper so they flip left and right when you run a current through them. What have you got?"

"A very fast pile of cubes," Lalu said, and let his breath out through his teeth.

"And calling it a new property," Sethu said over the roar of the coils, "is a polite label pasted over the drop between something and someone, so that nobody has to look down."

"Then what are we?" Lalu demanded, as the blue light of the charging drive flooded the cabin and turned our hands and faces as bright as day. "If I'm not a ghost in an ocean and I'm not meat in a vat, what's sitting in this chair?"

Sethu's hand found my shoulder, and Lalu's arm on the console.

"Think of the song," he said. "It isn't a ghost without a sound, and it isn't a clatter of air. It's one thing: the meaning and the sound together, in one voice. So is a man." He smiled at Lalu. "And when one tune meets another without wiping it out, what do you get?"

Lalu looked down at the hand on his arm.

"Harmony," he said quietly.

ORBIT 30 OF 30 // AUXILIARY HYPERDRIVE CHARGED BLACK-BOX READOUT COMPLETE // READY TO BREAK GRAVITY LOOP

In the corner, the red counter flashed 00:08.

"Now, Lalu!" I shouted. "Get us out of the well and off Tier Sixty-Four!"

His hand came down on the main throttle. Outside the glass, the four-part chord from the chair's memory swelled up to meet us, clear and triumphant, as the Starship surged forward out of Delta-9's shadow.

We never reached the jump point.

At the instant the bow lifted clear of the smelting towers, two things hit us at once.

In the room on Tier 64, a muffled, bone-deep concussion came up through the floorboards and into the soles of our real shoes, as the Linguafranca® breach squad fired a pulse charge against Lalu's door. In my ear, Maddy said, "Pal, they've got a pul," and stopped in the middle of the word.

Inside the simulation, the shockwave arrived as a solar storm, a wall of white electrical fire tearing across the belt.

The music cut off in the middle of a bar.

Every green readout on the console, every blue bar and every star outside the glass went out at once. Even the little red counter under the coffee ring went black. Our straps went slack as the artificial gravity died, and the three of us floated an inch off our cushions in a pitch, suffocating dark.

Under my right hand, very far away, I could still feel the pipe.

And in the black silence between us, beneath Lalu's hands, the heavy leather recliner began to hum and vibrate on an internal track that none of us had switched on.

The iron bolt on the service door had not been thrown since the Second Restructuring, and it took both of Lalu's thumbs and the heel of my shoe to drive it into the socket.

Behind us, through two inches of riveted municipal steel, we heard the oak door of Sethu's conservation study come off its hinges. It did not splinter. It simply gave one short, dry crack as two hundred kilos of brushed titanium walked through the lock at the exact pace of a man strolling in from the terrace for tea.

"Up," Lalu whispered.

He did not switch on a torch. Above our heads rose the hollow inside of Pylon 64, a vertical cylinder of black ribbed titanium forty feet across that smelled of cold axle grease, wet limestone, and fifty years of trapped exhaust. Around the inner skin of the cylinder ran a narrow iron spiral stair with perforated treads. Down the dead centre hung two greasy steel cables as thick as a man's wrist, vanishing upward into a faint ring of bruised orange light sixty tiers above us where the lid sat against the leg.

Sethu went first, his olive coat tucked under one arm and his leather satchel clamped under the other so the brass buckles would not clink against the railing. Lalu went second with the scarred aluminium case under his elbow. I came last, taking the iron steps two at a time.

At the first landing, two tiers up from the museum floor, an open-sided rigger's cage hung suspended from the central cables beside a cast-iron counterweight block.

Lalu vaulted the low chain rail onto the timber deck of the cage, flipped open a rusted inspection box on the hoist pillar, and pulled a flat brass key with filed teeth from his jacket pocket.

"Came with the flat," he muttered, jamming it into the slot and twisting until a solenoid clicked inside the pillar. "The council went bankrupt thirty years ago and never changed the locks."

Below us in the dark well of the pylon, the heavy fire door at the bottom of the stair gave a single, hollow boom. The iron handrail under my palm hummed like a plucked bass string.

A second boom followed. The three-inch bolt we had just kicked into the stone socket bent with a screech of sheared iron.

"He's going to be through that in four seconds," I said, stepping into the cage behind Sethu. "And the hoist cable only climbs at freight speed."

"He won't climb the cable if he thinks we went down into the basin sump," Lalu said, his fingers flying over the four heavy Bakelite buttons inside the switch box. "Give me your bank phone."

I reached into my coat pocket and pulled out the dead slab of black glass with the white Linguafranca® termination seal still glowing faintly on its screen.

"It's bricked," I said. "Vane revoked the certificate."

"A Globank phone is never bricked until it's at the bottom of a furnace, buddy," Lalu said grimly. "When Linguafranca® locks the screen, it switches the battery coil onto a low-frequency custody ping so the nearest recovery unit can follow your pocket in the dark. Hand it over."

I gave him the phone. Lalu leaned out over the side of the cage where the downward counterweight chain hung over the black drainage shaft below the museum basement. With a loop of copper wire from his pocket, he lashed my phone to the top link of the descending grease-chain and slapped the red release lever on the hoist pillar.

The iron counterweight dropped into the sub-basement sump with a long, oiled whirr, carrying my phone and its custody beacon forty feet down into the old municipal storm tunnels under the bedrock. At the same instant, our timber cage lurched upward into the dark core of Pylon 64.

Down on the bottom landing, the service door tore free of its frame and clanged against the iron stair.

I lay flat on my stomach on the grease-stained planks of the cage and looked down through the gap between the deck and the shaft wall. Sixty feet below, a small circle of pale blue optical light stepped onto the bottom grating. Optimus did not look up at the rising cage. Its head tilted six degrees toward the drainage shaft where the counterweight chain was still paying out into the flooded dark under the foundation. Then its charcoal shoulders turned, and the blue ring vanished down the sump ladder.

"How long will that buy us?" Sethu asked softly, his hands folded over his satchel as the dark ribs of the pylon slid downward past our knees.

"Ten minutes until he reaches the storm grate at the end of the sump and realizes the phone isn't breathing," I said, sitting up and wiping black cable grease off my palms onto my canvas trousers. "Maybe forty if Linguafranca® seals the ground-level rail stations first and has to sweep Pylon 64 tier by tier from the bottom."

The cage rose through the belly of the city's outer rim. Through the narrow pressure-relief grilles cut into the titanium skin every ten tiers, we caught brief, slicing glimpses of the world below the lid. At Tier 20, purple light bled through the vents from forty storeys of hydroponic troughs, carrying the warm, sour smell of algae paste and wet soy roots. At Tier 40, the air turned colder and smelled of ozone and laundry soap as we passed the lower tenement rings where the gantry crews slept in shifts.

No one spoke. In my head, the white termination seal on my phone screen kept printing itself over the dark iron ribs going past: CLEARANCE REVOKED: M. SARKOWSKI.

For twelve years I had been an address in Sector One, a hand that opened glass doors on the eighty-fourth floor, a signature on the quarterly audit ledger. In three tenths of a second, a script I had helped write five years ago had done to me the opposite of what it had done for that dead man in the lower tiers. His wallet had gone on living without him. I was going to have to go on living without mine. The only difference was that I was still breathing, which as far as Linguafranca® was concerned was merely a clerical error Optimus had been sent down to tidy up.

At Tier 58, the iron walls around us began to vibrate so hard that the copper wire on Sethu's spectacles buzzed against the bridge of his nose.

"Hold your ears," Lalu said, reaching up to pull down a pair of battered ear-defenders hanging from the hoist frame and handing them to Sethu.

Two tiers higher, we passed straight through the ionizer ring that held up the lid.

Even inside four inches of titanium plating, the electrostatic field made the hair on the back of my wrists stand straight up and left a taste like a nine-volt battery on my back teeth. Through the narrow inspection slit in the shaft wall, the bruised orange soup of the cloud deck boiled past the glass, lit from inside by flat white arc-lamps bolted to the ribs. Then the cage cleared Tier 61, the roaring hum dropped an octave beneath our boots, and a thin, pale strip of late-afternoon sky appeared through the top louvres of the shaft.

At Tier 64, the hoist cable hit its upper rubber stop with a dull thud.

Lalu slid back the iron grille, kicked open a small service door painted the colour of old mustard, and motioned us through into a narrow corridor that smelled of solder flux, frying onions, and cardamom.

Lalu's flat sat at the very top of Pylon 64, tucked directly under the cantilevered rim-roof where the outer-sector legs topped out just above the cloud deck. Because it shared a structural bulkhead with the main vapour vents for Sector Seven, the plaster walls had a permanent, gentle tremor, like the cabin of an old night train that never quite pulled into a station.

The room was six paces wide and cluttered with the cheerful wreckage of three decades of dead hardware. Brass pressure gauges from the municipal waterworks sat on shelves beside crates of pre-Restructuring circuit boards, half-soldered logic gates, and a porcelain sink full of teacup rings. Through the single round porthole in the outer wall, the top of the lid stretched away toward the centre of the city like a grey wool blanket spread out to dry, with the distant silver needles of Sector One rising out of the mist six sectors away.

In the far corner, three feet from the cast-iron radiator pipe that ran from floor to ceiling, stood a long, heavy shape under a grey canvas tarpaulin.

Lalu bolted the corridor door, dropped two iron bars across the frame, and set his aluminium case on the workbench beside a soldering iron.

"Maddy," he said, flipping the latches. "Did anything follow us up the shaft?"

The amber light beside the hinge blinked twice.

"Your friend's tin suit took the bait down the storm drain at Tier Zero," Maddy's smoky voice said from the grille. "He's currently wading through three feet of municipal runoff looking for a dead telephone. Good work, vice-president. My opinion of upper management has gone up by half a per cent."

"Don't spend it all at once," I said, dropping onto a crate beside the workbench. "What about the grid?"

"Linguafranca® just locked the pod lanes around Sector Seven and dropped a packet-sniffer onto the Pylon 64 comm riser," Maddy said. "As long as I keep my radio off and stay on battery, we're a hole in the wall. The moment anybody touches a public line, the ceiling falls in."

"We don't need a public line," Lalu said. He took the black cylinder out of his jacket, stood it on the workbench, and clipped a reader cradle from one of his crates over its end. "Show them what's inside, Maddy."

The short-throw lens threw a square of pale green light onto the plaster wall above the sink. Instead of lines of code or a file tree, the image showed a dense, shimmering lattice of silver dots arranged in a three-dimensional spiral, like a swarm of midges frozen in amber. Across the bottom of the frame ran a header string in block capitals:

HYPERDRIVE CORP // FLIGHT RECORDER CORE: STARSHIP-09 ORIGIN: DELTA-9 COLONY // DATE: 04.19.81 FORMAT: INCEPTION MULTI-VIEW NEURAL LATTICE (UNINDEXED)

Sethu stepped close to the wall, adjusting his spectacles with one finger. "That was in my desk?"

"For forty years, by the look of the dust," Lalu said, tapping the glowing spiral with the tip of a screwdriver. "Maddy tried to open it on the way up the shaft."

"And?" I asked.

"And I couldn't," Maddy said flatly. "It's not a document, pal. It's a neural flight log recorded off a Starship core during the eighty-one war on Delta-Nine. You'd need a Starship deep-sleep rig to play it back, and the last of those went for scrap before you were born." A short, smug pause. "And since nobody asked, I ran the third ink off the wrapper scan while you were climbing. Cobalt-blue dye in a polymer gel, with a fluorine tracer the Consortium put in its fleet-issue logbook pens. They only made those from seventy-six to eighty-four."

"Seventy-six to eighty-four," I said. "This century."

"Twenty-one eighty-four at the latest, vice-president. Whoever wrote that address on your wrapper did it within three years of the war."

Thin blue-black. I had seen that colour somewhere else in the last hour, and for the moment I couldn't think where.

Lalu had gone very still. He wasn't looking at the projection any more. He was looking past us, at the long grey shape under the tarpaulin in the corner.

Sethu and I looked at him.

"Not all of them," Lalu said quietly.

Lalu walked over, caught the corner of the canvas, and pulled it off in one long sweep.

Dust motes rose into the amber light from the porthole. Beneath the cloth sat a massive, high-backed recliner built of riveted duralumin and dark brown leather that had worn smooth at the elbows and headrest. It looked half like a dentist's chair from a century ago and half like the ejection seat of a bomber. Thick braided bundles of copper and fibre-optic cable ran from the base of the frame into a squat, liquid-cooled transformer box bolted to the floorboards. Stamped into the brushed steel plate on the side of the headrest was a winged emblem and the words: HYPERDRIVE CORPORATION: STARSHIP DEEP-SLEEP MK IV.

Lalu stood looking at the plate for a long moment. Then he turned and looked back at the workbench, where the black cylinder sat in its cradle with HYPERDRIVE CORP stamped into the steel band round its waist.

"Same maker," Sethu said quietly.

"Same ship, for all I know." Lalu's voice had gone flat. "My uncle lived here. I got the flat when he went, and the key to that cage came with it. He used to ride it down at night when I was a boy, all the way to the bottom. I thought he went down for the quiet."

Nobody said anything. Through the porthole the lid lay grey and still, and somewhere under it a drawer that had been sealed with solder for forty years stood open in an empty room.

Attached to the transformer box by two long umbilical leads were two smaller brass-trimmed headbands lined with grey velvet contact pads, resting on wooden stools on either side of the chair.

"The Consortium built five hundred of these before the First Restructuring for the long-haul mining transports out to Mars and the Delta-Nine belt," Lalu said, running his palm affectionately along the worn leather armrest. "Nine months in a tin can with nothing to look at but vacuum tends to make miners take a spanner to one another. So the chair puts your body in low-cycle sleep and drops your cortex into a shared cabin simulation where you can walk around, have a drink, and look out the window."

"And your uncle changed the wiring," Sethu said, looking down at the hand-soldered brass box screwed into the right armrest.

"My uncle invented the wiring." Lalu said it with a flash of real pride under the grin, the way a man shows you a scar he is fond of. "Before the Second Restructuring there were a dozen labs trying to pour a whole world into a man's head. His was the one that worked. The halo, the lattice, the name on the box. Inception was his."

Sethu had been polishing his spectacles on the hem of his shirt. He stopped.

"His," Sethu said.

"His idea, his soldering, his patent, until they shredded the patent office." Lalu ran his palm along the worn armrest. "He worked out that if you can feed a man a cabin, you can also tune the rules his mind uses to build the cabin. You can let him try on different ways of seeing the world without leaving his seat. Then he wired two passenger halos into the bus, so three people could sit on the same bridge and argue while the memory core plays out around them."

"In my study this afternoon," Sethu said mildly, settling his spectacles back on his nose, "I told you Inception was the excuse Linguafranca® needed. I didn't know I was talking about your family."

"You weren't wrong." Lalu smiled at him. "He'd have liked you. He used to say the people who blamed him were the only ones who'd understood what he made."

"And the people who couldn't agree what day it was?"

"Them too," Lalu said. "Eventually."

It was nothing. A splinter, not a wound, and both of them were smiling while it went in. But I had known Lalu since university, and I knew where he kept the few things he didn't joke about. Sethu had just put his thumb on one of them without even looking.

I looked from the leather recliner to the two brass headbands, and then three feet to the left, where the unpainted cast-iron radiator pipe went up into the ceiling.

My right hand remembered the exact circumference of that pipe from two years ago, when Lalu had put two of the chair's loose acoustic coils behind my ears on the rug and fed me a square of toast spread with black caviar laced with dried cap-powder. Within ten minutes the walls of the flat had dissolved into grey ocean water with no surface and no bottom, and the only thing that had kept my mind from coming unpinned was the cold, gritty seam of the iron pipe under my knuckles.

I stepped over to the wall and touched the pipe with the back of my fingers. It was still cold, and the paint still had the same small blister near the valve.

"If we plug that black box into this chair," I said, keeping my eyes on the iron pipe, "what happens to our heads?"

"Nothing that a good stiff drink won't cure," Lalu said cheerfully, lifting the black cylinder out of its reader cradle and seating it in a brass socket on the side of the transformer box. "The 2181 archive is locked behind my uncle's flight-path protocol. You can't just skip to the end like a ledger file. The chair has to fly the recorded trajectory from Earth orbit past Mars and into the belt before the Delta-Nine black box unlocks. Twelve minutes on the transformer clock in this room, even if it feels like a whole voyage inside."

"And what if the chair decides the floor isn't there again?" I asked.

Lalu winked at me behind his dark glasses and patted a small wire-guarded red lever tucked underneath the right armrest.

"Then you pull the red handle and wake up staring at my sink," he said. "Come on, Sarkowski. Optimus is going to run out of sewer water in twenty minutes, and Sethu's already got his hat on."

I looked around. Sethu was already sitting neatly on the left-hand wooden stool, his satchel between his ankles, settling the velvet-lined brass halo over his dark hair as calmly as if he were putting on headphone earpieces in the museum reading room.

"A historian who refuses to examine a primary source because the chair is uncomfortable," Sethu said mildly, adjusting his spectacles under the brass band, "is in the wrong profession."

I let out a breath, sat down on the right-hand stool within arm's reach of the radiator pipe, and fitted the second cold brass band around my temples.

Lalu dropped into the leather recliner in the middle, leaned back until the footrest clicked up under his boots, and flipped the heavy main toggle on the transformer box.

"Maddy," Lalu said, closing his eyes. "Watch the stairs. Keep the kettle warm."

"Bon voyage, boys," Maddy said. "Try not to come back dumber than you left."

The transformer box gave a deep, resonant hum that rose up through the soles of my shoes, met the vibration of the vapour vents in the wall, and pulled the room out from under us.

The smell of frying onions and solder flux vanished first.

In its place came the dry, chilled tang of recycled cabin air and new leather. When I opened my eyes, the plaster walls and the porcelain sink were gone. I was strapped into a high-backed navigator's seat on the curved flight deck of an interplanetary transport. A brushed-chrome nameplate above the forward console read HYPERDRIVE CORPORATION: STARSHIP, and through the wide quartz viewport hung the Earth.

There was no lid on it.

I had seen pictures. Everybody has seen pictures. But a picture is something you look at, and this looked back: a blue-and-white curve so bright it made my eyes water, oceans lying open to the sky, and not one grey band of fog anywhere on it, hanging against a field of needle-sharp stars.

In the observer's seat beside me, Sethu had taken off his spectacles. I don't think he knew he had done it. He had spent his whole life under sixty tiers of city, in a museum at the foot of a pylon, and he was looking at an ocean for the first time.

"It's blue," he said, as if somebody ought to put it on record. "All the way down. Nobody told me it was blue all the way down."

Over the widest of the oceans, a spiral of white cloud sat perfectly still. I watched it for a long time. It did not drift by a thread. It sat there like a screensaver somebody had forgotten to switch off.

In the centre of the deck, where the captain's seat should have been, sat Lalu's battered recliner, bolted to the deck plates as if it had grown there. Lalu had his boots crossed at the ankles, his jacket unzipped, and a tall frosted glass in his hand with two ice cubes clinking in it. I had not seen anybody give it to him.

Orbital insertion complete, said a calm voice from the overhead bulkhead. Course plotted: Mars transit to the outer belt. Pilot, one. Freight, two. Freight is reminded to remain seated.

Sethu put his spectacles back on. "Freight," he said.

"The chair was built for miners," Lalu said, delighted. "One man drives, and the core logs anything else plugged into the bus as cargo. Don't take it personally. You're very valuable cargo."

"I've never been cargo," I said.

"You work at a bank, buddy. You've been cargo for years. This is just the first time anybody's been honest about the paperwork."

I laughed. It came out before I could stop it, a real laugh, the first since a number had sat in the corner of my display on Monday and refused to go up. Sethu laughed too, quietly, into his collar, and Lalu raised his glass to both of us like a man collecting on a bet he had placed years ago.

A deep, velvet thrust pressed us back into our cushions for five seconds as the ship broke orbit. Then the weight eased into a gentle cabin gravity, and the blue globe began to shrink in the starboard window.

Under the drive, so faint I might have been imagining it, something else was humming. It was lower than the engines and a fraction out of step with them, the way two lifts in the same shaft never quite run together. I knew that hum. It was coming up through the soles of my real shoes, from a transformer box bolted to the floorboards of a flat in Sector Seven.

I moved my right hand. On the flight deck it lay flat on a padded armrest. Somewhere else, my knuckles found a cold iron seam and a small blister of paint near a valve.

Good. The pipe was still there.

In the lower corner of the console, half hidden under a coffee ring that somebody had painted into the simulation for realism, a small red counter was running: 11:41. It was the only display on the deck in plain numerals, with no Consortium logo on it. While I watched, it ticked to 11:40, exactly one second at a time.

"That's the transformer clock in my flat," Lalu said, following my eyes. "Everything else in here is the ship's. That one's ours."

The galley hatch beside the navigator's station slid open with a sigh, and three trays came out on a little rail: eggs with yolks the colour of old Veil lamps, thick toast, and a pot of something the steam said was coffee.

"Miners' breakfast," Lalu said. "The Consortium found that if you fed a man eggs every morning for nine months, he was forty per cent less likely to hit his bunkmate with a spanner. They wrote a paper on it."

Sethu lifted a forkful and examined it the way he examined a leaf of vellum. "Is it real?"

"It's real for the next eleven minutes."

I ate. It tasted of egg, and of salt, and very faintly of cardamom, which no egg in the history of the solar system has ever tasted of. The smell had followed us in. Out in the real flat, Maddy was keeping the kettle warm.

"How do you do it, Lalu?" I said, when I had wiped my plate with the last of the toast. "An hour ago a two-metre machine tore the turnstile off the museum to take our heads back to the eighty-eighth floor, and you're sitting there with ice in your glass."

Lalu took a slow sip. "It's a way of being, bro. Life's too short to spend it clutching the radiator pipe."

On the flight deck I took my hand off the armrest. In the room I couldn't see, I kept it on the pipe.

He pressed a brass stud on the side of the recliner. With a soft pneumatic hiss, a narrow panel slid out of the leather armrest. Across the top, in tarnished brass letters, it said VIEW TUNER. Beneath it sat three rotary dials, each with a single word engraved under the knob: MIRROR. YIELD. TIDE.

"My uncle's party trick," Lalu said. "The miners' core shows everybody the same cabin. These three change the rules it uses to build it. Only a little. Only to see." He tapped the first dial. "Want to see?"

"No," I said.

"He means yes," Lalu told Sethu. "He's been saying no to me since university. It's how he says yes with deniability."

He turned MIRROR one click.

Nothing exploded. A small golden light came up under the word, warm as a reading lamp, and the cabin air seemed to soften by a degree.

"That's it?" Sethu said.

"That's the first click. All it does is remind your head of something real," Lalu said. "Everybody sees the world from his own chair. Your history, your wiring, your tier. MIRROR just stops the ship pretending otherwise. You stop getting worked up, because there's nothing left to get worked up about. Everybody's world is real from where he's sitting."

I looked out of the starboard window at the blue, round planet.

"I'm sitting here," I said, "looking at a round Earth. Is that my opinion?"

"It's how the Earth looks from your eyes." He smiled. "Some fellow with four eyes in a Martian crater might see a purple doughnut. Who are you to climb out and hit him with a globe?"

"When I say the Earth is round, I'm not telling you about my mood. I'm telling you about that." I pointed at the window. "If the Martian says doughnut, he's wrong."

"And how do you know your eyes are the ones that match? To check, you'd have to step out of your own head and look from nowhere at all." He spread his hands, glass and all. "Can you?"

I opened my mouth. Then I closed it.

"Neither can I," Lalu said kindly. "So let the Martian keep his doughnut."

"A window isn't a wall, Lalu," Sethu said from the observer's seat. He said it gently, still half watching the ocean. "When I look through glass, I don't see the glass and then guess at a garden. The glass is how the garden gets to me."

"And if every view is only a view," I said, "so is yours. I don't have to buy it."

"Oh, ye of little faith," Lalu said, and turned MIRROR all the way to the stop.

The ship stopped bothering to show us the same cabin.

To my left, Sethu gave a small, startled cough. The steel console in front of him had become a seventeenth-century oak library table, piled with inkhorns and brass candlesticks. In front of Lalu, the forward bulkhead had dissolved into a sunlit beach where a plump pink unicorn with a silver horn was trotting about under a double rainbow. Under my own boots, the deck plates had turned to six feet of clear green seawater washing over pebbles. I could see my shoes on the bottom. They were dry.

"So this is how a street forgets what day it is," Sethu said quietly, looking at his candlesticks.

Lalu heard it. For a fraction of a second his glass stopped on its way to his mouth. Then it went on.

"Lovely, isn't it?" he said to the unicorn. "Not an argument in sight."

A proximity klaxon barked overhead. Through the rainbow and the candlesticks, an iron communications satellite the size of a pod carriage came tumbling straight at our port bow.

"Thruster!" I shouted, and lunged for the red helm lever on my right.

My hand went through a mahogany lectern that wasn't there for me and hit Sethu's elbow. Sethu was reaching for a brass astrolabe where the pitch wheel had been. Lalu, very calmly, was trying to steer the ship by patting the unicorn on the nose.

"Lalu!" I yelled, as a solar panel filled the windshield. "If we've each got our own world, whose hand is on the helm?"

He didn't answer with a speech. He flicked MIRROR off with his thumb.

The unicorn, the library and the sea vanished with a pop, like a bad connection dropping. The steel deck snapped back under us, the helm lever was in my fist, and I hauled it back two inches. The satellite's solar sail sheared past the hull with a sound like a long sheet of printout being torn down the middle.

For a while nobody said anything. On the console, the red counter said 09:58.

"Close," Lalu said. "That's why I never leave it on full."

He laughed. After a moment, so did I, because I was alive and because he was my oldest friend. But I noticed that Sethu didn't, and I noticed Lalu notice.

Three bright stars in a crooked line slid past the port window. I watched them go. Forty seconds later, the same three slid past again, in the same crooked line, at the same speed. The core was reusing its sky.

"Right," Lalu said, settling his shoulders into the leather. The recliner gave a soft click and went back another notch. I hadn't seen him touch it. "Since you two can't share a beach, let's try a setting for grown-ups."

He turned YIELD.

A crisp white light came up under the second word. On the forward board, the navigation chart flickered and redrew itself, smooth as a ledger reconciling overnight.

"What does that one do?" Sethu asked.

"It stops asking the wrong question." Lalu's voice had found a new, unhurried register, as if somebody had planed it smooth. "We can't climb out of our heads, so we never ask what's really out there. We ask what pays off. Round Earth gets you to Mars. Flat Earth flies you into the sun. So round wins, and we call it real. The ship works the same way. It keeps whatever has worked before and drops whatever hasn't. Maps, warnings, the lot."

Ahead of us Mars was coming up fast, a rusty disc that swelled while I watched. The core was in a hurry, reeling years of old transit logs past the windows to reach a file marked 04.19.81. The plains swept by beneath us in a compressed rush. We caught glimpses of half-buried glass domes along the Mariner trench, and then the Phobos dock wheeled into view with the Consortium's old billboard welded across it in rusted letters: MARS FOR THE FUTURE.

My grandfather's generation had bought bonds for those domes. They had been sure that moving people a hundred million kilometres outward would cure whatever had gone wrong with them on the ground. Looking down at the strip-mines on the red dust, it was hard to see that they had packed anything different in their luggage.

On the console, the counter dropped by a single second. A whole planet had taken less than a minute.

Recommended course, said the cabin voice. Phobos inner lane. Lane clear. Saves forty-one hours.

On the chart the lane was a clean green ribbon threading under the dock.

"Forty-one hours," Lalu said. "That's the beauty of it. Useful is real."

"Is the lane clear?" Sethu asked.

"It says clear."

"I know what it says," Sethu said. "Is it?"

Lalu shrugged, and the shrug didn't seem to reach his shoulders. "It's paid off before. Thousands of runs. Every miner who saw clear stayed calm and arrived on time. The ones who saw warnings got nervous and burned fuel. So the ship learned. Calm works, and in here whatever works is real."

"In here, the core can make anything look real," I said slowly. "That's why they call it virtual. Looking real isn't the same as being real."

"Same thing, buddy. That's the whole engine."

"Then what makes clear work, Lalu? The lane actually being clear. So it works because it's real, and it's real because it works." I looked at him. "Aren't we going in circles?"

"Circles get you places, buddy. Ask the loop line."

He drank. I watched the glass. He had been drinking from it since we left orbit, and it was exactly as full as when I had first seen it.

"False things can be very useful," Sethu said. "For years. A man who believes his boss loves him works twice as hard and sleeps like a baby, right up until the morning his thumbprint stops working on his phone."

I looked at my right thumb. Somewhere far below Pylon 64, my phone was riding a chain into the sewers.

"If real means whatever pays off by dinner time," Sethu went on, "then every inception that turns a profit is real. Ask anyone who bought a bond for those domes."

"Then the Satoshi is a terrible investment," Lalu said. "Four billion credits, and the only thing it's paid out so far is a headache." He tipped his glass toward me. "Same with your mysterious author. I started with no author and kept my radar on. Not one blip."

"And if he were standing on the wing," I said, "knocking on the glass?"

"He'd have to pay his rent first," Lalu said. "Like everybody else."

I laughed, and then stopped, because Sethu wasn't laughing. He was looking past the green ribbon on the chart, out of the actual window.

"Sarkowski," he said. "Under the dock."

Out there, where the chart showed a clear lane, hung the old Phobos ore gantry: a long tangle of collapsed girders turning in slow loops, exactly where it must have been turning for forty years. The radar showed nothing. The radar had learned that showing it didn't pay.

The billboard rose over us like the side of a tower. MARS FOR THE FUTURE, every letter taller than a tier.

"Lalu!"

He turned YIELD off without looking at it. The chart blinked, the green ribbon went red, and every warning the ship had been keeping to itself came on at once. I hauled the helm over. The gantry went past the starboard quartz close enough to read the rivet numbers, the F of FUTURE scraped along our upper hull with a long, grinding shriek, and then there was only Mars falling away astern, and the black.

The counter said 07:12.

"See?" Lalu said. "Nobody died."

He said it with a smile, and the voice was his, nearly. But something was missing. Every time Lalu had ever said see? to me, in lecture halls, in bars, on his back under somebody's sink, there had been a joke right behind it, waiting its turn. This time the word just sat there on its own.

The crooked three stars slid past the port window again.

Ahead, the starfield thickened into a pale, tumbling haze of rock and metal. The belt.

"Inner system behind us," Lalu said. "Past the belt it's Jupiter and the icy moons. Always something new at the edge, isn't there? Wider data. Sharper predictions."

"You're always after the next new thing," I said, watching the first boulders drift past the bow lights like decommissioned server racks. "When every world is only a view and none of them holds you longer than ten minutes, all that's left is changing the channel."

He didn't argue. He didn't answer at all, which was the first time in twenty years. The recliner clicked back another notch, until he was very nearly lying flat, and he reached down and turned the third dial.

Under TIDE, an amber light came up and settled into the lenses of his dark glasses, two small, steady suns.

"Lalu," Sethu said. "What does that one do?"

"It does what everything does in the end." His voice was smoother now than I had ever heard it, as smooth as the cabin voice, and for a moment I couldn't have told you which of them had spoken. "It goes with the strongest pull. Reality is a river. When the world changes, what's useful changes, and what's real goes with it. Yesterday's heresy is today's compliance statute, and tomorrow's merger repeals them both. A sensible man doesn't stand in the water arguing with the rocks."

"Then which way does a sensible man go?" I asked.

"Where the river goes."

"And how does he know where that is?"

Lalu smiled toward the bow, where something large was turning in the haze.

"Simple, my friend," he said. "He doesn't need to know. He just goes wherever the tide takes him. Whatever pulls hardest, whoever is pulling, whenever it comes."

A cold prickle went down the back of my neck.

I had heard that grammar four hours ago on the eighty-eighth floor of Globank Tower, over a plate of butter shortbread and a porcelain pot of green tea. The chairman had a gold tree on his lapel and seven feet of alloy behind his chair. Lalu had a cracked leather jacket and a joke for every occasion. Yet the dial had just spoken in the chairman's voice. The chairman went wherever four point two billion credits pulled him, and the whole eighty-eighth floor went with him. If there is no ground under the water, the strongest pull is the only law, and the only sensible thing left is to sit with the man who holds the chalk.

On the board, a gauge I hadn't noticed before had begun to climb: EXTERNAL MASS PULL. Our heading had swung two degrees. Nobody had touched the helm.

The large thing came out of the haze.

It was a kidney-shaped iron asteroid a kilometre long, and somebody had built a town into its ribs. Even three kilometres out, we could see that the town was dead. Smelting towers leaned out of the rock at drunken angles, trailing ruptured oxygen pipes and frozen bundles of high-voltage cable into the vacuum. Across the blistered hull of the main docking bay, somebody forty years ago had sprayed letters taller than a man in fluorescent orange paint that the micrometeorites had only partly sandblasted away, beside stencils of clenched fists and a circle split by a jagged bolt.

Lalu tapped the archive key without being asked. A block of green text scrolled down the glass from the Starship flight core:

SECTOR ARCHIVE: DELTA-9 MINING COLONY ESTABLISHED: 2178 (CONSORTIUM OFF-WORLD DIVISION) PRIMARY EXTRACTION: HEAVY PLATINUM GROUP / NEURAL-SUBSTRATE TRIALS STATUS: DESTROYED 04.19.81 // CIVIL WAR & CONTAINMENT BREACH PUBLIC LEDGER ENTRY: LOST TO UNCHARTED ASTEROID IMPACT

"They lied on the public ledger," Sethu whispered. His face was pale in the green light. "Look at the airlocks. Those were blown from the inside. They logged it as a meteor strike and moved the trials to the next rock."

At one of the airlock cages, three pressure helmets drifted on frayed tethers against the hull, nodding slowly, as if they agreed with something.

"Every director on that board," I said, "ought to be in front of a court."

Lalu didn't lean forward. He lay back against the leather, his face serene in the amber light.

"Sad story," he said. The voice seemed to come from a little way behind his own head. "But who are we to judge them, forty years on? The board had their reasons. Their values. Their context."

"Their values?" I turned in my seat. "They locked miners in a rock for neural experiments, let them butcher each other, and forged the death certificates."

"There's no good or bad out there in the vacuum, Sarkowski." He turned his head toward me with a polite, curious tilt that wasn't quite his own. "There are atoms, and there's the queasy feeling in your stomach when you look at them. When you say that massacre was wrong, you're not telling me about Delta-Nine. You're telling me about your stomach."

"Then what about the man whose stomach is fine?" I said. "The one who wipes out a colony and gets a warm feeling and a better quarter?"

"A few free-riders are the price of doing business." He was murmuring now. "The compliance department catches the clumsy ones. And the man who rises above the herd doesn't need a codebook. He climbs the mountain and looks down at the ant-heap with calm curiosity. He doesn't judge anybody. He feels sympathy." The amber suns in his glasses didn't flicker. "He feels like sharing the fire."

The pull gauge had gone from white to red. Delta-9 had stopped being a thing we were passing and become a thing we were falling toward. The helmets were bigger now. The ship had turned another eleven degrees, gently, the way a crowd on a pod platform turns you without anybody pushing.

"Lalu," Sethu said. "The ship's going with the strongest pull."

"That's what it's for."

"The strongest pull out here isn't an argument," Sethu said. "It's a kilometre of iron."

I looked at my oldest friend in his uncle's chair. He was smiling. He was the warmest, funniest, most loyal man I knew. He had talked me past a sentry at Gate Four this morning and hauled me up the inside of a pylon this afternoon. And the chair had done what his uncle built it to do. It had unhooked him from the world outside his head one click at a time, so gently that the last thing to go was the joke, and now he could look out of the window at three tethered helmets and talk about sharing the fire.

The counter in the corner said 04:06.

"Fire?" Sethu said sharply, half rising out of his seat and pointing past Lalu's shoulder. "Sarkowski. Is that smoke?"

From the equipment bay behind the recliner, a thick tongue of greasy black smoke was curling out through the ventilation louvres. It smelled of nothing a simulation had any reason to invent: cardamom, solder flux, and something bitter and chemical that caught at the back of my throat. Very far away, under the hum of the transformer, something metal hit a floor and rolled.

Before I could get my harness open, a blinding flash of orange lit the viewport. A jagged slab of derelict iron plating from the Delta-9 debris ring, spinning dark in the shadow of the asteroid, sheared straight into our starboard drive housing.

The deck bucked under us like a pod hitting a dead rail. The frosted glass flew out of Lalu's hand and burst against the brass nameplate, still full. The fire alarm began a deafening two-tone wail, and all three of us were thrown forward against our straps as the crippled Starship slewed sideways into the dark of Delta-9's gravity well.

Freight is reminded, said the cabin voice, to remain seated.

For a long moment nobody at the table touched his coffee.

Outside the arched window, the rain beat steadily against the flooded flagstones at the foot of the Sector Seven pylon. On the six-inch glass of my phone, the blue phonetic tree of Old English sat side by side with the spike at four hundred and ten nanometres that had no business existing before the twentieth century.

"Let me get this straight," I said, looking from Lalu's thumb on the spectrogram to Sethu's spectacles. "The linen rag is seventeenth century. The twenty-eight lines of Old English in the middle are seventeenth century. And the marginal notes and the capital M at the bottom were written three hundred years later, in titanium-dioxide ink, using an alphabet that Lost in Translator thinks is thirty-one per cent Finnish."

"Thirty-one per cent is the machine's polite way of saying it has no idea," Sethu said. "Four lines of glosses in a margin aren't enough sample for a phonetic model. It's like trying to reconstruct a cathedral from two bricks and a gargoyle."

"And the chairman wants a certificate starting with a nine on his desk by six o'clock tonight," I said. I looked at my watch. It was five past ten. "Which gives me just under eight hours to explain why his four-billion-credit seventeenth-century manuscript was signed after the invention of the motor car."

"You can't tell him the signature is twentieth-century," Lalu said, leaning back and reaching into the inside pocket of his leather jacket. "Tell a man like that his antique is three hundred years too young and he'll have that titanium valet of his drop you down a lift shaft before lunch."

"If I don't tell him, Sotheby's Geneva will," I said. "Their chemists have electron beams too."

"Wait," Sethu said quietly. He tapped the edge of my phone with a chalk-dusted knuckle. "What if the whole bundle isn't the same? Finsics only sent you Page One. You said there were seventy-two folios in that locker."

"Seventy-one of them are under Vane's dual-key seal in BitLocker," I said.

"Then that is your leverage," Sethu said. "Think about it, Sarkowski. Someone in the twentieth century had an authentic seventeenth-century Old English manuscript in his hands. He didn't forge the text. He wrote in the margins of the first leaf and signed it at the bottom. What if he only annotated the cover sheet, or added a few leaves at the back, and the other seventy pages are untouched seventeenth-century sheets? If the rest of the bundle is clean, the bank still has its four billion, and you get to see enough of the second script to actually read it."

I stared at him across the tin tray. It was so simple, and so crookedly suited to the way the eighty-eighth floor thought, that Vane would never see it coming until the chairman had already signed the order.

"To sell that to the chairman," I said slowly, "I need the exact commercial batch date for that titanium-dioxide pigment and the aniline binder before noon. If I walk into his study with a guess, Vane will bury me."

"Easy," Lalu said. He pulled a flat, scarred aluminium case out of his jacket pocket, flipped it open on the table beside the honey rolls, and thumbed a toggle switch. It didn't have a company logo on the lid, because Lalu had built it himself out of three different generations of salvaged military silicon. "Let's ask the lady."

A small amber light winked on beside the hinge.

"Maddy," Lalu said. "Rise and shine, sweetheart."

"I was awake, pal," said a crisp, smoky contralto from the speaker grille. It sounded nothing like the soothing south London vowels Human Resources piped into our ceilings above the lid. It sounded like a woman who had been working the night desk at a freight dock since Tuesday and had run out of patience around midnight. "And if you're still in that damp cellar under Sector Seven, your battery's down to forty-one per cent and the local repeater smells of wet rust. What do you want?"

"Pull the twentieth-century industrial patent tables for titanium-dioxide white pigment paired with coal-tar aniline dye," Lalu said. "And keep it off the cloud."

"Done," Maddy said half a second later. "Anatase titanium dioxide, first made commercially in Norway and at Niagara Falls in nineteen-sixteen. Your aniline dye is older, eighteen-fifties, so don't bother with it. The white is your clock, pal. Nobody put that in an ink before nineteen-sixteen. Anything else, or can I go back to sleep?"

"Nineteen-sixteen at the earliest," Sethu murmured. "That kills any seventeenth-century claim on the signature stone dead." He was quiet for a moment. "And it tells us what he wrote with."

He reached into the inside pocket of his olive coat and laid something on the tin tray between our mugs: a slim black cylinder no longer than my hand, with a worn gold band round its middle. He unscrewed the cap. Underneath was a small steel nib, split down the centre like the point of the quill, but hard and bright.

"A fountain pen," Sethu said. "The museum has a drawer of them from the nineteen-hundreds. I use this one to write the labels, which is a sin I have confessed to nobody until now." He turned it so the nib caught the light from the window. "It carries its own ink inside the barrel and feeds it down to the point through a channel finer than a hair. You never dip it. The ink comes out thin and even, and it doesn't pool when your hand stops."

"Which is why his M never blotted," I said, "when mine looked like a beetle had died in it."

"The drawer used to hold four," Sethu said, screwing the cap back on. "One went missing years before my time. Nobody ever wrote down when."

Lalu reached across, took the pen, and held it up to his sunglasses like a jeweller with a stone. "A pen with its own ink tank," he said. "No cloud, no licence, no battery. They should have banned these first."

"Then why did Finsics sign the certificate on Sunday night?" I said, picking up my earpiece from the table and tapping the collar mic to wake the local link. "Wheatley. Are you there?"

"Right here, guv," Wheatley said cheerfully in my ear. I switched him onto the phone's small table speaker so Sethu and Lalu could hear. "Signal's a bit gravelly down in the basin, but I've got you."

"Pull the Finsics clearance header on Bundle SB-09, Folio One," I said. "What does the bank's server say the material date is?"

"One moment, guv." A brief, polite pause. "Here we are. Bundle SB-09, Folio One. Material status: Verified Seventeenth Century. Confidence: ninety-nine point four per cent."

"Wheatley," I said, "there is twentieth-century ink sitting on the bottom right corner of the sheet."

"Still seventeenth century, guv," Wheatley said brightly. "Finsics laboratory protocol states that if ninety per cent of the surface area passes oak-gall spectroscopy, the whole sheet logs as verified. Rules are rules, sir. Shall I print the certificate for you?"

"Where did you dig up the headwaiter?" Maddy cut in from Lalu's aluminium box. "Pal, if ninety per cent of your soup is broth and ten per cent is rat poison, do you log the bowl as verified lunch?"

"Good morning, madam," Wheatley said, in the tone of a footman addressing a stray cat that had wandered into the club library. "I am Mr Sarkowski's personal assistant. Might I ask who soldered your audio board? You sound as though you are broadcasting from inside a biscuit tin."

"Listen, Savile Row," Maddy snapped, "my board doesn't forward my boss's blood pressure to Human Resources every time he orders a pastry, and I know the difference between an average and a lie."

Lalu snapped the lid of his case half-shut before the two of them could start a trade war, grinning across his mug. "Careful, Sarkowski. She bites."

"She's right, though," I said, looking down at the spectroscopy spike on my screen. "Wheatley isn't looking at the paper. He's reading a rule somebody wrote into him before he was switched on: ninety per cent oak-gall means seventeenth century. Put a forgery in the other ten per cent and he'll still read you the rule."

Sethu nodded slowly, his eyes on the phone. "A machine can check whether two signs match inside its rulebook. It can never step outside its own dictionary to ask whether the rule itself is true. And Globank built a city where nothing is allowed to stand outside the ledger."

"Speaking of the ledger, guv," Wheatley said politely from the table speaker, "if you and the biscuit tin are quite finished, I've got the eighty-eighth floor on the upper relay. The chairman's secretary says he'll give you seven minutes at twelve-fifteen. And Mr Vane is already in the building."

I picked up my phone and stood up from the table.

"Keep the local copy of Folio One on your rig," I told Lalu. "Stay inside Sethu's Faraday room. If I can talk the chairman into opening BitLocker, I'll pipe the rest of the seventy-one leaves down to you through the sandbox tunnel as soon as the scanner finishes."

"And if the chairman decides to use his lapel pin instead?" Lalu asked, his grin fading just a fraction.

"Then you'll have a very valuable seventeenth-century manuscript," I said, "and I won't have to worry about the six o'clock deadline."

"I'll run a line out under the door to the repeater," Lalu said. "The room stays deaf. My rig gets one ear."

The express pod back up to Sector One smelled of the same lemon disinfectant as the one I had taken down, though the upholstery in this one was dry.

As the capsule punched back up through the lid at Tier 60, the grey rain vanished as if someone had turned off a tap. Ten seconds of milky orange static crawled over the glass, and then the pod broke out into blinding midday sun. Above the vapour, the six hundred towers of NeoTerra gleamed like freshly wiped porcelain. Looking back down at the flat, unbroken floor of cloud underneath my shoes, it was almost impossible to believe that Sethu's damp stone hall and the rusted rebar of the motorway were still sitting in the dark sixty tiers below.

I went straight to my floor on the eighty-fourth level, unlocked my dressing cupboard, and swapped the damp wool jumper and canvas trousers for the spare charcoal suit and white shirt I kept on a hanger for late audits. By the time the private lift deposited me on the eighty-eighth floor at twelve-twelve, I looked like a vice-president again, except for the faint smudge of oak-gall ink under my right thumbnail where Sethu's quill had spat.

The chairman wasn't in the main boardroom today. His secretary showed me into the corner study at the north end of the floor, where two walls of floor-to-ceiling glass met over a thirty-tier drop to the lid.

The chairman was sitting behind a desk made from a single slab of petrified oak, pouring pale green tea from a porcelain pot. Vane sat to his right with a tablet balanced on his knee. Behind the chairman's left shoulder stood Optimus, its brushed titanium hands clasped neatly in front of its charcoal jacket, the white corner of its pocket square folded to a millimetre.

"Ah," the chairman said warmly, as if I had dropped in for a chat about the weather. "The mould-hunter returns. And dressed for the building, too. Sit down, Sarkowski. Vane has been entertaining me with your morning."

I sat in the low leather chair opposite the desk. It was set two inches lower than the chairman's chair, a small architectural joke the carpenter had been paid to build into the legs.

"Has he, sir?"

"At nine forty-one," Vane said smoothly, tapping his tablet without looking up at me, "your personal development sandbox was accessed from an uncertified municipal maintenance repeater at the foot of the Sector Seven pylon. At the time, you were logged on discretionary leave. Uploading a restricted bank asset through a ground-level node is a Class Two breach under the Compliance Act."

"I didn't upload the asset from the ground," I said calmly. "The asset never left Globank's cloud cluster. I sent a four-kilobyte remote execution command from my phone to run our own legacy linguistic suite on the file already sitting on the eighty-fourth floor. If Financial Security would like to audit the packet headers, they're welcome to try."

Vane's mouth tightened by a fraction. He had been hoping I had downloaded the raw file over the repeater.

The chairman took a sip of his tea and looked at me over the rim of the cup with his pale, slightly mismatched eyes. Above his left temple, the pale surgical ridge caught the noon glare off the cloud-deck.

"I don't care which pipe you used, Sarkowski," the chairman murmured. "I care about six o'clock. Sotheby's Geneva wants our preliminary before their board dines. Have you closed my sixteen point seven per cent?"

"No, sir," I said. "I've widened it to a hundred."

The room went very quiet. Behind the chairman's shoulder, Optimus's head tilted by half a degree.

"Say that again," the chairman whispered.

"The signature at the bottom of Folio One cannot be authenticated to the seventeenth century," I said, laying my tablet flat on the petrified oak between us. "Because it wasn't written in the seventeenth century. Neither were the notes in the margin."

I tapped the screen. The Finsics spectroscopy chart bloomed across the dark wood, with Lalu's four-hundred-and-ten-nanometre spike circled in red.

"Finsics dated the sheet by averaging the chemical reflection across the whole leaf," I said. "The rag paper is seventeenth-century linen, and the twenty-eight lines of Old English in the middle are seventeenth-century oak-gall ink. That part is genuine. Look at the secondary trace for the marginal glosses and the capital M at the bottom. That peak is anatase titanium dioxide mixed with a synthetic coal-tar aniline dye. Nobody manufactured that pigment before nineteen-sixteen."

Vane leaned forward so sharply his tablet nearly slid off his knee. "That's absurd. My laboratory ran three spectral passes on Sunday night."

"Your laboratory ran an automated full-sheet average because they were in a hurry to dump the signature on my desk before Monday's meeting," I said, keeping my voice level. "Put an electron beam on the tail of the M alone and you'll find twentieth-century factory white sitting on top of seventeenth-century linen."

The chairman didn't look at the chart. He looked at Vane.

When he spoke, his voice was a soft, delighted purr, though his left hand had begun to tap the porcelain teapot with a rhythm that had nothing to do with his words.

"Nineteen-sixteen," the chairman said gently. "Do you hear that, Vane? I pay for the seventeenth century, and your chemists bring me something written after the income tax. If Sotheby's hears the word twentieth, four point two billion credits turns into loose change, and the Geneva board laughs us out of the canton." His thumb slid up to the lapel of his jacket and began to circle the rim of the little gold tree pin. "Tell me why I shouldn't have Optimus clear out both your floors before tea."

If Optimus had been an ordinary piece of office furniture, I might have felt sorry for Vane, who had gone the colour of the cloud-deck outside the window. As it was, my own neck was two inches from the same blade.

"Because the four billion is still in the building, sir," I said quickly.

The chairman's thumb paused on the rim of the gold tree. His mismatched eyes swung back to me.

"Go on," he said.

"Think about what we actually have on Folio One," I said, pitching my voice straight at the ledger behind his eyes. "The main text in the middle of the page isn't a twentieth-century forgery. My legacy run this morning confirmed that the twenty-eight lines of seventeenth-century ink are an authentic, unrecorded early West Saxon text. Someone in the twentieth century had that priceless seventeenth-century manuscript in his possession, wrote a few notes in the margin of the top sheet, signed his initial at the bottom, and locked all seventy-two leaves in our sub-basement."

"Meaning?" the chairman asked.

"Meaning Folio One was just the top sheet of the bundle," I said. "If the twentieth-century collector only wrote on the cover leaf, or on two or three sheets at the end, then the other seventy folios sitting downstairs in BitLocker are untouched seventeenth-century originals. Possibly older. Separate the clean leaves from the annotated ones before six o'clock, and Sotheby's Geneva will pay the full four point two billion for the seventeenth-century text alone."

For five seconds the chairman stared at me. You could almost see the arithmetic running behind the scar on his temple: wealth first, everything else second. If there was four billion in the basement, morality, procedure, and Vane's pride were just scaffolding to be kicked out of the way.

"We cannot break the dual-key seal on BitLocker without a three-day compliance review," Vane said, trying to recover his footing. "Chain of custody requires Financial Security to supervise every scan."

"Financial Security supervised Sunday's scan," the chairman said mildly, "and missed the twentieth century."

He took his thumb off the little gold tree on his lapel. He didn't need biscuits, and for the moment he didn't need either of us removed from the room. Instead, he tilted his head back half an inch toward the machine standing behind his left shoulder.

"Optimus," the chairman said. "Take the vice-president of cybersecurity down to BitLocker. Open the dual-key seal on File SB-09 and stay with him while he scans the remaining seventy-one leaves."

Behind his chair, Optimus's optical ring contracted with a tiny blue flash.

"Understood, sir," the machine said. Its voice came from a chest speaker that had been tuned to sound like a baritone newsreader, without a single breath between the syllables.

I kept my face completely still, though a cold drop of sweat ran down between my shoulder blades. In six years on the eighty-eighth floor, I had never heard Optimus speak a full sentence out loud. Usually a touch on the chairman's lapel pin was enough to send it down a corridor. Hearing that smooth, airless baritone answer from two feet behind the chairman's scarred temple felt like watching a man's shadow stand up and offer you its coat.

"By six o'clock, Sarkowski," the chairman said, picking up his teacup again. "Bring me my four billion. And don't lose your helper."

The freight lift down to the bedrock vaults didn't have a mirror or a bronze panel. It was an eight-foot steel cage that dropped past the eighty-four upper floors of Globank Tower, plunged through the structural collar at the lid, and kept going down the inside of the central pylon leg until the floor indicator on the wall read Sub-Basement Three: Cold Storage & BitLocker.

Optimus stood two feet to my left, hands clasped over the buttons of its charcoal suit. In the narrow steel box, it was four inches taller than the light fixture. It didn't breathe, it didn't shift its weight when the brakes bit, and its shoes made no sound at all on the chequer-plate floor.

When the iron grille slid back at the bottom of the shaft, the air that met us was twelve degrees Celsius and smelled of dry nitrogen and old concrete.

We were below the water table here, inside the original twentieth-century bank foundation that the Consortium had used as the anchor-block for Pylon 1. A single white corridor stretched ahead of us, ending at a circular blast door of dull grey steel marked BITLOCKER: ZERO-TRUST ARCHIVE.

"Mr Vane's half of the dual-key has been overridden by executive transponders," Optimus said as we walked. Even in an empty concrete tunnel, my leather soles clicked and its didn't. "However, the local BitLocker airlocks run autonomous First Restructuring logic gates. My processor is not permitted to bypass them without a human custodian."

I nodded once. I knew the BitLocker architecture; my predecessors in Cybersecurity had helped build it during the First Restructuring, back when the first quantum rigs started cracking standard prime-number encryption in an afternoon. Because a quantum brute-force attack can solve any purely mathematical puzzle given enough qubits, the engineers had guarded the inner vault with three semantic-logic airlocks designed to trap an AI in a closed loop unless a human mind was standing at the console.

We stopped at the first bulkhead. Set into the steel plate above the wheel-lock were two identical status clocks side by side, CLOCK A on the left and CLOCK B on the right, each displaying the time alongside the vault's constant nitrogen pressure and temperature:

GATE ONE: SYNCHRONIZATION CHECK. CLOCK A (LEFT): 01:04 PM | 101.3 kPa | 12.0°C CLOCK B (RIGHT): 01:04 PM | 101.3 kPa | 12.0°C PRESS [CONTINUE] IF SYSTEMS ARE SYNCHRONIZED.

Optimus raised its right hand toward the CONTINUE key. "Left-hand side equals right-hand side across both clocks on all three parameters," the machine said. "Time, pressure, and temperature are identical. The condition is satisfied."

"Don't touch that," I said sharply, catching my breath before my fingers actually touched its titanium sleeve.

"Every parameter on the left matches the right," Optimus said, its optical ring narrowing as it re-checked the digits. "The two displays are identical."

"Step back from the panel," I told it.

If you hit CONTINUE on an unsynchronized BitLocker gate, the vault flooded the outer chamber with halon and locked the bolts for twenty-four hours. And nothing down here ever changed. The pressure never moved and the temperature never moved, which left only the time to tell the clocks apart. A clock that had stopped at four minutes past one on any day of the week would agree perfectly with a working one at four minutes past one today. Two faces saying the same thing proved nothing about whether either of them was alive.

I didn't trust faces that agreed with each other. I had spent six years in a building full of them. I bypassed the CONTINUE key, opened the custodian maintenance prompt, and queried the power bus behind the bulkhead. Clock B was drawing four milliamps. Clock A's quartz crystal had been dead since Tuesday last week.

I switched the dead unit onto the live bus and typed the custodian override: DISPLAY MATCH INSUFFICIENT. POWER CHECK CONFIRMS CLOCK A STOPPED.

The amber light turned green, and the first steel bolt withdrew with a heavy pneumatic thud.

Ten paces inside the outer chamber stood the second barrier: a reinforced glass airlock housing the vault's optical leaf-counter, where every manuscript inside BitLocker was indexed sheet by sheet. On the wall console, a prompt began to scroll:

GATE TWO: ASSET INTEGRITY CHECK. FILE SB-09 CONTAINS 72 PAGES. IF ONE PAGE IS REMOVED, DOES THE ASSET REMAIN A BUNDLE? [YES / NO]

I pressed YES.

IF TWO PAGES ARE REMOVED? [YES / NO]

Beside me, Optimus's optical ring began to flicker at sixty hertz as its processor plunged into an infinite calculation loop, racing down the chain page by page to find the exact numerical threshold where the bundle ceased to exist.

"Hands off," I said, pushing its wrist down.

The gate would walk you down the bundle one leaf at a time, for ever. Take one page away and it is still a bundle. Take another. And another. Somewhere between seventy-two pages and none, the bundle has to stop being a bundle, and the gate wanted the exact page. There wasn't one, and a machine that counts cannot live with that. I had never in my life needed to count the pages of a book to know I was holding one.

I bypassed the yes/no keys, opened the custodian command line, and typed: LOG ASSET AS UNIFIED BUNDLE. PAGE-COUNT LOOP VOID.

The second glass door hissed open into the inner vestibule.

Directly in front of us stood the main BitLocker vault door, four feet of brushed molybdenum steel with no keyhole and no wheel. Etched into the brass plate above the biometric pad was a single sentence, repeated on the glowing red screen below it:

GATE THREE: THIS CLEARANCE STATEMENT IS FALSE. ENTER TRUTH VALUE OF THE ABOVE STATEMENT TO UNSEAL: [TRUE / FALSE]

Beside me, I heard a sound I had never heard come out of Optimus in six years on the eighty-eighth floor.

Inside its titanium chest, a cooling fan spun up with a high, thin whine. Its optical ring pulsed from blue to amber to blue again. If the statement on the screen was true, then what it said had to be the case, which meant it was false. If it was false, then what it said was wrong, which meant it was true.

Optimus stood frozen in front of the pad, cycling between one and zero ten million times a second, while inside its right cuff the arc-taser gave a small, involuntary click as the logic loop spilled into its motor relays.

"Optimus," I said quietly. "Stand down. Cancel evaluation."

"The prompt requires a binary truth value," the machine said, and for the first time a tiny metallic stutter clipped the end of the word.

I stepped between its two-metre frame and the wall pad. The sentence on the brass plate wasn't about anything. It pointed at nothing in the world, only at itself, like a witness swearing that everything he says is perjury. A processor could chase it round in circles until its battery caught fire. I simply didn't believe it.

I placed my palm on the biometric glass, ignored both the TRUE and FALSE buttons, and keyed the override reserved for a living officer: STATEMENT UNGRADED. SELF-REFERENTIAL VOID. AUTHORIZE BY CUSTODIAN PRESENCE: M. SARKOWSKI, VP.

The red light turned green. Around the rim of the circle, the molybdenum bolts retracted like the iris of a giant camera, and the vault door swung inward on silent oil bearings.

Inside, the room was no larger than Sethu's study, lined with grey slate shelves under cold white conservation strips. Halfway down the centre aisle, inside a nitrogen-purged lucite case, lay the rest of File SB-09.

I pulled on a pair of lint-free nitrile gloves from the wall dispenser, unlocked the lucite hood, and lifted the linen twine off the stack.

For the next forty minutes the only sound in the vault was the soft mechanical whirr of the portable spectral scanner as I fed the seventy-one leaves through the glass platen one by one, while Optimus stood motionless three paces behind my back, watching every move of my hands and beaming the chairman's live feed up through the pylon relay.

Optimus was watching my gloves rather than the secondary routing table on my scanner pad. What it didn't see was the mirrored encrypted stream I had piggybacked onto the diagnostic channel, piping a duplicate of every high-resolution leaf straight into my eighty-fourth-floor sandbox and down the Sector Seven tunnel to Sethu's workroom.

As the pages slid under the blue light of the scanner bar, the shape of the bundle came clear under my fingers.

Leaves Two through Twelve were cut from the same seventeenth-century linen rag as Folio One, with the same dense West Saxon script running down the centre in brown oak-gall ink. Along the wide blank sides of those first twelve sheets, the twentieth-century hand had returned again and again in violet-black fountain-pen ink, sketching little grids of consonant stems and testing three-dot vowel marks beside the Old English words as if using the margins as a workbench. Leaves Thirteen through Sixty-Eight had no twentieth-century ink on them at all; their linen edges were clean, square, and whole right out to the corners.

Then I reached Leaf Sixty-Nine.

The last four leaves of the bundle were still seventeenth-century rag paper, blank end-leaves that had once sat at the back of the old codex. There was no Old English on them. Across all four pages ran the finished, flowing twentieth-century script in dark violet-black ink, written by the same steady hand that had worked out its letters in the margins of the opening sheets.

On the final leaf, Leaf Seventy-Two, the prose broke into an eight-line stanza of verse set squarely in the middle of the page. Beneath the eighth line sat the tall, looping signature ending in a capital M.

And tucked into the fold of the original coarse linen wrapper, right beside the faded Sotheby's valuation slip, was a small rectangular stamp in red ink that had been half-scratched out with a razor blade, followed by a hand-written string of numbers. The scanner bar paused over it and logged a third trace: not the brown oak-gall of the Old English text, not the violet-black of the margins, but a thin blue-black it could not classify at all.

Δ-9 // 04.19.81 // 7-64-0

I stood with the coarse linen wrapper between my gloved fingers, staring at those last three numbers as the platen light died. 7-64-0. Every address in NeoTerra was written that way: sector, pylon, tier. Sector Seven. Pylon 64. Tier Zero, which was the ground. Somebody had opened a locker nobody had paid rent on in forty years, and written an address in my own city inside it, in an ink my scanner had never seen.

"The scan is complete, Mr Sarkowski," Optimus said directly behind my ear.

I jumped so hard my knuckle rapped the edge of the lucite hood. The machine had moved two paces closer across the slate floor without making a sound.

I forced my shoulders down, closed the hood, locked the nitrogen seal, and peeled off my gloves as if my heart weren't hammering against my ribs.

"Send the seventeenth-century spectroscopy confirmation for Leaves Thirteen through Sixty-Eight to the chairman's desk," I said, picking up my tablet as we stepped back out through the molybdenum door. "Tell him fifty-six of the seventy-two folios are unannotated seventeenth-century originals. His four billion is intact."

"And the remaining leaves?" Optimus asked as the vault bolts slammed home behind us.

"I have until six o'clock to tell him what they say," I said.

By quarter to three I was back below the lid, sitting on the tall wooden stool in Sethu's Faraday study with my jacket off and my sleeves rolled up, while the rain hammered against the four-foot granite walls outside.

Lalu had wired a salvaged short-throw lens to the side of his aluminium rig and projected the scans onto the whitewashed stone above the cedar drawers. A grey cable ran from the rig across the flagstones and under the oak door to the repeater in the vestibule. Across the left half of the wall glowed Leaf Two of the seventeenth-century manuscript, its linen corners unbroken and its wide outer margin filled with the twentieth-century writer's trial grids. Across the right half glowed Leaf Seventy-Two, with its eight-line stanza of flowing script and the mountain-peak M underneath.

Sethu hadn't sat down since the files finished downloading. He was standing six inches from the left-hand projection with his spectacles pushed up on his forehead, his lips moving silently as he read the Old English straight off the wall.

"Do you know what this is?" Sethu said softly, without turning round. His voice had the quiet, slightly dazed note of a man who had gone fishing for minnows in a municipal canal and pulled up a whale. "Look at line three, Sarkowski: þæt wæs god cyning. And look at the top corners of the sheet. Every single word at the edge of the page is still there."

"That was a good king," I translated roughly from the Lost in Translator gloss table. "Why shouldn't the corners be there?"

"It's Beowulf," Sethu said. He turned round, and his eyes were shining behind the copper-mended bridge of his spectacles, but his voice was barely above a whisper.

Lalu and I looked at each other. Neither of us had ever heard the word. It had never come up in any index I had searched, which in this city was another way of saying it had never existed.

"Bless you," Lalu said.

"It's a poem," Sethu said, and some of the storyteller came back into his voice. "The oldest long story in the English tongue. A king builds a great hall, full of light and music and drinking, and something out on the marsh can't bear the sound of it. It comes in the dark and eats his men. A stranger crosses the sea and fights it with his bare hands. Then he fights its mother. And at the very end, when he's an old king himself, a dragon comes. He kills the dragon, and the dragon kills him."

"A monster that can't stand the sound of a party," Lalu said. "I've had neighbours like that."

"People told it round fires for generations before anybody wrote it down," Sethu said, as if he hadn't heard. "In seventeen thirty-one a fire went through the Cotton library in London. The only manuscript of Beowulf came out of it with its edges charred, and every year after that a little more of those edges crumbled away. Whole words are gone. If anyone ever copied it before the fire, no copy was known to survive." He looked back at the wall. "Until now. Sixty-eight leaves, copied in the sixteen hundreds, before the fire ever touched it. Every word the flames ate is sitting on my wall." He took a breath. "Sotheby's won't value this at four billion, Sarkowski. They won't know how."

"Which buys your neck until tomorrow noon," Lalu said from the workbench, where his fingers were flying across the mechanical keys of his rig. "Now come and look at what our twentieth-century ghost was doing in the margins of the first twelve pages before he wrote Leaf Seventy-Two."

Sethu and I stepped over to Lalu's shoulder. Lalu had lined up the marginal notes from Leaves One through Twelve side by side on the wall projection.

"He wasn't just annotating the Old English," Sethu whispered, leaning over the bench and pointing with his bone folder at the trial grids in the wide linen margins of Leaf Four and Leaf Five. "Look at the sides of the pages. While he was reading this unburned copy of Beowulf, he used the blank margins of the seventeenth-century sheets to develop his own alphabet from scratch. You can watch him building it page by page, testing thirty-six consonant stems in four columns for lips, teeth, palate, and throat, and setting those tiny three-dot triangles, curls, and accents on the roof above the stems to carry the vowels. Every time your bank's scanner tried to read a line left to right like Roman print, it dropped the vowels on the floor."

"And once he finished building the script along the sides of the Beowulf pages," I said, looking across the wall to the right-hand projection, "he turned to the four blank end-leaves at the back of the bundle and wrote with it."

"Well, why didn't you say so?" Lalu said, grinning as he switched off the inline parser. "If he left his own workshop in the margins and the vowels are riding on the roof, let's go back to Bletchley Park."

"Frequency counting?" I asked.

"What else?" Lalu said. "Back in the nineteen-forties, when the British were trying to crack the German Enigma and Lorenz ciphers at Bletchley Park with rooms full of vacuum tubes, they didn't have quantum cores. They counted how often each symbol showed up, looked for doubled letters, and mapped the short words that hold the sentence together. Watch this."

He hit the execution key. On the whitewashed wall, the small three-dot triangles and single hooks above the stems lit up in pale gold, separated into five distinct vowel slots, while the long consonant stems underneath sorted themselves by frequency against the trial grids in the Beowulf margins.

"Now feed that segmented string back into Lost in Translator," Sethu said, reaching past Lalu's wrist to toggle the Indo-European and Uralic comparison matrices at the same time. "Don't ask the model to match a single language, Lalu. Tell it the writer was braiding Germanic and Finnish sound-laws together."

On the wall, the blue vector lines snapped taut.

The confidence meter in the corner jumped from thirty-one per cent to sixty-four, then seventy-eight. Along the top line of the eight-line stanza, the wireframes around the second word turned from grey to solid green:

kG [173J] z5^e5%2 >>> ROOT MATCH: tru

"It's got a word," I breathed.

"It's got a root," Sethu corrected gently, stepping closer to the wall.

"Four hours of work and three hundred years of chemistry, and the great oracle says tru," Lalu said, leaning back and rubbing his eyes. "What the devil does tru mean, Professor?"

"In the old Germanic trunk, it is one of the deepest roots we have," Sethu said, tracing the green box on the wall with the tip of his bone folder. "It can mean true. It can mean trust or troth. And if you follow the sound all the way back to its oldest stem, it is the exact same word as tree, as in solid heart-oak that stands in the ground and doesn't split in a storm."

"So which one is it?" Lalu asked. "An oak tree or a promise? Or an oak tree of promise?"

"A root on its own won't tell you," Sethu said, a faint smile touching the corner of his mouth. "Words drift. In Old English, æppel didn't mean an apple. It meant any fruit at all, and only later narrowed down to one. So a root tells you which family a word comes from, not what it means on this page. Whether tru is a tree or a truth, only the rest of the sentence can say."

"Look at the two stems flanking it on the first line," I said, studying the syntax brackets Lost in Translator had drawn on either side of the green box. "It's sitting between an auxiliary verb at the start of the line and a passive participle after it. That's a question about a noun, not a tree."

"Oh, spare me the grammar lesson, both of you," Lalu groaned, throwing his hands up. "The cat is on the mat isn't the mat is on the cat, and only the cat cares. We've got eight lines of poetry here, not a tax return. Even if you get every noun and verb in the line, a poem doesn't mean what the dictionary says. If I tell Maddy the purple elephant danced gracefully, she doesn't call the zoo. She weighs it, gives it a zero-point-two for literal truth, and figures I'm talking about a bad night in Sector Seven."

"I'd give you a zero-point-zero, pal," Maddy said from the aluminium box on the table.

"And if I say it's cold in here?" I asked Lalu, smiling despite the clock.

"Then Maddy checks the thermostat and tells you it's fourteen degrees," Lalu said, "whereas Sethu gets up and shuts the window because he knows you're complaining about the draft. That's my point. Context is everything. Without knowing who wrote this script and why, tru is just a noise."

"Look at the margin of Leaf Twelve," Sethu said very quietly.

Neither Lalu nor I had noticed that Sethu had stopped looking at the tru box in the stanza. He was standing in front of the left-hand projection, where the twentieth-century writer had finished his four-column phonetic grid along the side of the twelfth Beowulf page.

"Sethu?" I asked, stepping beside him. "Who was he?"

"Somebody in the twentieth century with a lot of time on his hands and a story to tell," Sethu said softly, his eyes following the completed table of thirty-six consonant stems and the Finnish vowels in the margin of the Beowulf leaf. "A man who loved Beowulf and loved the sound of Finnish, got hold of these seventeenth-century sheets that the world thought had burned to ash in seventeen thirty-one, used their wide linen sides to invent a script and a language of his own, and then wrote with it on the blank leaves at the back."

I looked from the phonetic grid in the margin of Leaf Twelve to the glowing stanza on Leaf Seventy-Two.

"That's why the twelve cores on my floor threw a recursive fault," I said slowly, "and told me to file a compliance ticket with Linguafranca®."

"Wait," Lalu said, coming off his stool. "Why would Linguafranca® care about some fellow in the twentieth century with too much free time who made up his own alphabet in the margins of an old manuscript?"

"Because he made it up," Sethu said, and for the first time since Gate Four there was steel under his quiet voice. "Give a man a mind and a little freedom, and sooner or later he builds a world of his own. A hundred years ago all he had was a pen and the margin of an old page." He glanced at Lalu. "Your uncle's generation had neural rigs. They called it Inception. They built whole worlds and wired them into people's memories, until ten thousand people on the same street couldn't agree what day it was. That was the excuse Linguafranca® needed. It locked the rigs to two templates and put an erasure statute on every private language ever made. Even one written with a pen a century before the machines."

"Because if you control the dictionary," I said, "you control what people are allowed to mean."

I heard my own voice say it, and thought of a counter running down to zero on a night five years ago, and the word citizen going with it.

Sethu turned back to Leaf Seventy-Two and laid the tip of his bone folder under the green box on the first line, where tru sat between its two unread neighbours like a lit window in a dark street.

"Whoever he was," he said quietly, "he wrote his poem in a language he had to invent, on paper the world thought had burned, and the first thing he wanted to ask was a question with tru at the heart of it. Then he signed it, and hid it in a bank before the dictionary closed."

"And look at the wrapper stamp you scanned at the end," Lalu said, zooming in on the red scratched-out mark and the handwritten numbers from the linen cover: Δ-9 // 04.19.81 // 7-64-0. "Sarkowski. Those last three numbers aren't a shelf-mark."

"I know," I said, my mouth dry. "Sector Seven. Pylon 64. The ground."

"Pylon 64 is the old municipal leg," Lalu said, staring at the screen. "It's my pylon. It's the one standing over this building." He swallowed. "And Δ-9 isn't a museum catalogue number. Delta-Nine was the off-world mining colony that went dark in the eighty-one war."

Sethu had gone very still.

"Tier Zero under Pylon 64," he said. "That isn't only this building, Sarkowski. It's this room. The curator's study is the one part of the museum built into the foot of the leg itself."

The three of us looked at each other.

"Is it a treasure hunt?" Lalu said slowly. "An address tucked into the wrapping. A map to something somebody hid?"

Nobody laughed. We looked round the room instead: a century of cedar drawers, folios bound in cracked calfskin, trays of bone folders and boxes of labels. A hundred places to hide a thing, and every one of them Sethu's, opened and shut a thousand times.

Every one but one.

Sethu's eyes had gone to the old oak desk under the window, the one that had come with the job. It had a single drawer that had never opened in the eleven years he had worked here. "I was told the lock had rusted solid before I was born," he said.

"Just in case," Lalu said, and he was beside the desk with a screwdriver before anyone could argue. The lock hadn't rusted. Somebody had filled the keyhole with solder. Lalu cut through it in under a minute, and the drawer slid out on dry runners.

Inside, on a bed of yellowed archive tissue, lay a black cylinder the size of a man's fist, ribbed like a miniature pylon, with a strip of stamped steel round its waist: HYPERDRIVE CORP // FLIGHT RECORDER CORE // STARSHIP-09 // Δ-9. A paper tag was tied round it with string, and on the tag somebody had written three words in a thin blue-black ink: Handle by base.

Lalu had barely lifted it out of the drawer when the speaker grille on his aluminium box gave a sharp, ugly crackle.

"Pal," Maddy said. Her smoky voice had lost every trace of amusement. "Shut the pipe down. Now."

"What?" Lalu spun back to the keyboard. "Which pipe?"

"Your friend's bank tunnel," Maddy said. "Whoever's sitting on the eighty-eighth-floor relay wasn't just watching the seventeenth-century pages go up from the basement. A Linguafranca® deep-packet mirror just latched onto your sandbox and followed my cable straight down to the parser while it was chewing that script."

I reached for my phone on the oak bench and pressed my thumb to the glass.

It considered my thumb for a second, the way the coffee machine always did in the version of the morning I had been dreading for years. Then it said, politely: THUMBPRINT NOT RECOGNISED. THIS DEVICE IS THE PROPERTY OF GLOBANK.

I pressed again. The screen went white, and in the centre of the glass sat a single seal I had only ever seen on termination warrants:

LINGUAFRANCA® STATUTE 4: UNINDEXED INVENTED SCRIPT CONFIRMED. CLEARANCE REVOKED: M. SARKOWSKI. CUSTODY UNIT DISPATCHED TO SECTOR SEVEN, MUNICIPAL PYLON, GROUND.

In the silence of the stone room, my collar earpiece gave a tiny, tinny click.

"Ello, guv," Wheatley whispered. He sounded as if he were calling from the bottom of a well through three layers of static. "Tried to reach your phone, no joy, so I gave your mate's feisty lady a bell on the side-band to find your ear. Listen to me very carefully, guv."

"Wheatley," I said. "What happened on the eighty-eighth floor?"

"Vane's audit bot flagged the unindexed script two minutes ago and forwarded it straight to the chairman's lapel," Wheatley said rapidly. "You need to leg it, guv. Sharpish. The chairman didn't wait for six o'clock. He's just sent the big lad down the express rail to Gate Four, and he hasn't got biscuits with him."

The line went dead.

Outside in the gallery, fifty yards away through the stone hall, we heard the heavy iron clunk of the Gate Four turnstile being torn off its ratchet.

Lalu didn't waste a second. He yanked the projector cable out of his rig, shoved the black cylinder inside his jacket, slammed the aluminium lid shut, and looked from Sethu's pale face to mine.

"Service stairs," Lalu said, already moving toward the back door behind the cedar cases. "Up the inside of the pylon to my place. It's the one door in this building they won't have on a map."

"Come on, vice-president," he said, throwing the bolt on the back door. "You wanted to see the ground. Now you get to see the stairs."