For the first gigasec, we pursue the war by traditional methods. We find half-forgotten T-gates leading into polities under the control of Curious Yellow. We go through, shoot up the a.s.semblers theyare using as immigration firewalls, establish a toehold, fight our way in, install sanitized A-gates of our own, and forcibly run the civilian population through them to remove the Curious Yellow taint from their heads. The ones who survive usually thank us afterward.

At first itas relatively easy, but later we find we are attacking polities where the defenses are heavier, and later still Curious Yellow starts programming the civilians to fight bitterly and without quarter. Iave seen naked children, shaking in the grip of an existential breakdown, walking toward panzers with Vorpal blades clutched inexpertly in both hands. And Iave seen worse things than that. The idea of Curious Yellow, of surrender to a higher cause, seems to appeal to a certain small subset of humanity. These people manipulate the worm, customizing its payload to establish quisling dictatorships in its shadow, and the horrors these gauleiters invent in its service are far worse than the crude but direct tactics the original worm used.

Quite late on in the campaign I realize this and, in a fitful flashback to my earlier self, I begin to spend some of my spare time thinking about the implications. My study of the psychology of collaboration becomes one of the most heavily accessed stacks in the Catsa internal knowledge base. So it probably shouldnat come as a surprise when I receive a summons to headquarters, combined with orders to converge my deltas and revert to orthohuman skin before transit.

At first Iam apprehensive. Iave grown used to being an armored battalion, spending most of my seconds between action in icy orbit around a convenient failed star or exoplanet. Breathing and eating and sleeping and emoting are worrying, senseless handicaps. I recognize that they are of interest in comprehending the enemy motivational framework, and allowances must be made for them among the people we liberate, but why should I subject myself to the frailties of flesh? But eventually I realize that itas not about me. I need to be able to work with the headquarters staff. So I reconverge my various selves, erasing my ident.i.ty from the kilotons of heavy metal that have until so recently been my limbs, and I report to the nearest field command node for up-processing.

WHEN I come to, I find Iam leaning over the A-gate control panel. In my left hand Iam clutching a dripping knife so tightly that my fingers are close to cramping. Thereas blood halfway across the room, forming an obscene lake.

If I got it right, he wonat have had time to use his netlink. Heall have been in acute physical agony as his head came out of the bag, then heall have blacked out because of blood loss. Unconsciousness within ten seconds: Itas more than he deserved.

But now Iave got a huge problem, namely a hundred and ten kilos of dead meat lying in about ten liters of gore in the middle of a gra.s.s carpet thatas already dying. Is this incriminating or what? Oh, and my sweater and skirt and sensible shoes are covered in blood. This does not look good.

I laugh, and it comes out as a hysterical giggle with more than a little madness in it. This is bad, I think. But thereas got to be somethinga"

For a moment I flash back to the time with the malfunctioning A-gate, the pools of fluid and lumps of deanimated meat. That helps stabilize me, in a way: It makes it clear what I have to do. I pick up Fioreas arm and give it an experimental tug. His sallow flesh ripples, and when I put my back into it, he jerks free of the carpet and skids a few centimeters toward me. I grunt and tug again, but itas not easy to move him so I pause for a bit and look around. Thereas some kind of cabling on one of the tool shelves, so I go over and grab a couple of meters of wire, twine it around his torso under the arms, and use it to pull him toward the A-gate. Finally, I get him into position, back inside the gate chamber. Itas hard to keep him insidea"one leg keeps flopping outa"but eventually I figure out that I can hold him in if I use the rest of the cable to truss him up.

aOkay, take five,a I tell myself breathlessly, bending over the field terminal. Talking to yourself, Reeve? I ask ironically. Are we going mad, yet? My fingers leave sticky reddish smears on it as I prod at virtch controls, but eventually I manage to bring up the conversational interface. The gate seems to have a load of scheduled background synthesis jobs queued up, but itas mult.i.tasking, and this is an interrupt: aGate accept raw waste feedstock for disa.s.sembly okay.a aOkay,a says the gate, and the door whines slightly as it seals around the evidence.

aGate select template cleaning systems index that there, I want one of them, make me one of them okay.a aOkay, fabricating,a says the gate. aTime to completion, three hundred and fifty seconds after end of current job.a Ah, the conveniences of modern life.

I go upstairs to the common room and make myself a cup of tea.

While itas brewing, I strip off my outer clothes and drop them in the sink. Weave got some basic cleaning equipment, and the detergent is pretty good at getting out stains, probably better than anything they had in the real dark ages. A couple of rinses, and my skirt and sweater are simply soaking wet, so I wring them out and drape them over the thermal vent and dial up the air temperature.

Back downstairs, I find the A-gate gaping open and the stuff I asked for sitting inside it. Fiore has been transformed into a carpet cleaning machine and a bunch of absorbent towels. It takes another trip upstairs to fill its tank with water. The smell of solvents makes me dizzy, but after half an hour Iave gotten the visible bloodstains out of the carpet and off the walls and shelves. I canat easily do anything about the ceiling tiles, but unless you knew someone had been killed in here youad just mistake the spots for a leak upstairs. So I put the carpet cleaner back in the gate and talk to myself.

aItas a blind,a I say, then yawn. It must be the adrenaline rush finally subsiding. aFiore, Yourdon, and the other one. Psywar specialists working on emergent group behavior controls.a The blackouts seems to have jostled free some more fragmentary memories, dossiers ona"aWar criminals. Ran the security apparat for the Third Peopleas Glorious Future Sphere. When the vermifuge was released, they went on the run. Theyave spent the past gigasecs working on a countervermifuge, then on a way to harden Curious Yellow.a I blink. Is this me, talking? Or a different me, using my speech centers to communicate with the rest ofa"whoever I am?

aPriority. Exfiltration. Priority. Exfiltration.a My hands are moving over the gate control systems even without me willing them. as.h.i.t!a I yelp. But thereas no stopping them, they know what theyare doing. They seem to be setting up an output program.

aSystem unavailable,a says the gate, its tone of voice flat and unapologetic. aLongjump grid connectivity unavailable.a Whatever my hands are doing, it doesnat seem to work. Something has shaken loose inside my memory, something vast and ugly. aYou must escape, Reeve,a I hear my own voice telling me. aThis program will auto-erase in sixty seconds. Network connectivity to external manifold is not available from this location. You must escape. Auto-erase in fifty-five seconds.a Even though Iam only wearing clothes-liners, I break out in a cold sweat up and down my spine. aWho are you?a I whisper.

aThis program will auto-erase in fifty seconds,a something inside me replies.

aOkay, I hear you! Iam going, Iam going already!a Iam terrified that when it says this program it means mea"obviously itas some kind of parasite payload, like the Curious Yellow boot kernel. But where can I escape to? I look up, at the ceiling, and it clicks into place. I need to go up, through the walls of the world. Maybe, just maybe, this polity is interleaved with othersa"if so, if I can just break into an upper or lower deck, there may be a way to get to a T-gate and rejoin the manifold of the Invisible Republic. aGoing up, right?a aThis program will auto-erase in thirty seconds. Escape vector approved. Conversational interface terminated.a It goes very quiet in my head; I stand over the a.s.sembler terminal shivering, taking rapid shallow breaths. A shadow seems to have pa.s.sed from my mind, leaving only a cautious peace behind. The horror I feel is hollow, now, an existential dreada"So they hid zombie code inside me? Whoever they were?a"but Iam back, Iam still me. Iam not going to suddenly stop existing, to be replaced by a smiling meat puppet wearing my body. It was just an escape package, configured to report home after a preset period or some level of stress if I couldnat figure out what to do. When it couldnat dial out, it issued a callback to me, the conscious cover, and told me what it wanted. Which is fine. If I do what it wants and escape, then I can get any other little pa.s.sengers dug out of my skull and everything will be great! And I want to escape anyway, donat I? Donat I? Think happy thoughts.

af.u.c.k, I just killed Fiore,a I whisper. aIave got to get out of here! What am I doing?a Upstairs, the common room is as steamy as a sauna. Coughing and choking I dial down the heat, grab my damp clothes, and pull them on, then head for the door. Thena"this is the hardest parta"I pat my hair into order, pick up my bag, and calmly walk across the front lot toward the curb to hail a pa.s.sing taxi.

aTake me home,a I tell the driver, teeth nearly chattering with fear.

Home, the house Iave shared with Sam for long enough to make it feel like somewhere I know, is a scant five minutes away by taxi. It feels like itas halfway to the next star system. aWait here,a I tell the driver. I get out and head for the garage. I donat want to see Sam, I really hope heas at worka"if he sees me, I might not be able to go through with this. Or even worse, he might get dragged in. But heas not around, and I manage to get into the garage and pick up my cordless hammer drill, a bunch of spare bits, and some other handy gadgets I laid aside against a rainy day. I go back to the taxi, and Iam still tightening the belt to hang everything off when it moves away.

We cruise up a residential street, low houses set back from the road behind white picket fences, separated by trees. Itas hot outside, loud with the background creaking of arthropods. We drive into a tunnel entrance. I take a deep breath. aNew orders. Stop right here and wait sixty seconds. Then drive through the tunnel and keep going. Keep your radio turned off. At each road intersection, pick a direction at random and keep driving. Do not stop, other than to avoid obstructions. Accept one thousand units of credit. Continue driving until my credit expires. Confirm.a I bite my lower lip.

aWait sixty seconds. Drive, turning randomly at each intersection, until credit limit exceeded. Avoid obstacles. Confirm?a aDo it!a I say, then I open the door and pile out into the tunnel mouth with my kit. I wait tensely as the zombie drives off, then I start walking back into the blackness.

The tunnel darkens as it curves, and I pull the big metal flashlight out. Like everything else here, itas probably not authentic, no electrochemical batteriesa"the same infrastellar T-gate that powers cars or starships will suffice to provide a trickle of current to a white diode plate. Right now, thatas good news. I shine it at the walls to either side as I walk, until I come to one of the recessed doors. Unlike the last time I came this way, Iam prepared for it. Out comes the hammer drill, and I only spend a few seconds sliding a stone bit into ita"all that time in the garage has paid off, I guess. The racket it makes as it bites and chews at the concrete next to the door is deafening, but chunks of synrock fall away, and the air fills with acrid dust that bites at my lungs when I inhale. Should have brought a mask, I realize, but itas a bit late now, and anyway, the sound and feel of the drill is changing as the bit skitters across bright metal. aHah!a I mutter, resisting the frantic itch that keeps prodding me to look over my shoulder.

It takes me a couple of minutes to get enough of the surface of the doorframe exposed to be sure what Iam looking at, but the more I see, the happier I am. The concrete tunnel is a hollow tube, and the door is some kind of inspection hatch near a join. If Iam right, the join isnat a T-gate, itas a physical bulkhead designed to seal segments off in event of a pressure breach, which means this is part of a larger physical structure. This door will lead into the pressure door mechanism, and maybe via an airlock into other adjacent segmentsa"up and down as well as fore and aft, I hope. The only problem is, the dooras locked.

I dig around in my pockets for one of the toys I took from the garage. Chopped-up magnesium from a block the hiking shop sold me, mixed with deliberately rusted iron filings in a candle-wax basea"a crude thermite charge. I stick a gobbet of the stuff above the lock mechanism (which is annoyingly anch.o.r.ed in the concrete), flick my lighter under it, then jerk my hand back and turn away fast. Even with my eyelids tightly shut the flare is blindingly intense, leaving purple afterimages of the outline of my arm. Thereas a loud hissing sputter, and I wait for a slow count of thirty before I turn round and push hard on the door. It refuses to budge for a moment, then silently gives way. The lock is a glowing hole in the partially exposed doorframea"I hope we donat have a pressure excursion anytime soon.

I step through the door and glance around. Iam in a small room with some kind of crude-looking machine occupying most of it. Gas bottles, axles, physical valves. It looks as if it was built during the stone age and designed to be maintained using tools from the hardware store. Maybe it was? I scratch my head. If this hab was originally configured for some kind of paleo cult, made to resemble one of the polities of old Urth, it would be relatively easy for Yourdon and Fiore to tailor to their purposes, wouldnat it? Maybe thatas what old-me meant about this place having unique features suiting it to their needs. Thereas a ladder, of all things, bolted to the wall, and a hatch in the floor. I go over to the hatch in the floor, which is secured by a handwheel. Turning the wheel isnat too hard, and after a moment thereas a faint breeze as the hatch rises and rotates out of the way.

Hmm. Thereas a pressure imbalance, but itas nothing major. That means open doorways, maybe a whole deck down below. But I said Iad go up, didnat I? I start to climb. The hatch in the ceiling has another wheel, and it takes me longer to rotate it, but thereas some sort of spring mechanism inside it that raises it out of the way. Thatas smart design for you. They a.s.sume that pressure breaches come from outside, which in a rotating cylinder hab like this means down, so you have to exert force to open a hatch leading down. But hatches leading up have a pa.s.sive power a.s.sist to make it easy to get away from the blowout. I like that philosophy: Itas going to make life ever so much easier.

I climb into the tunnel, then pause to pull my headlamp on. Getting it lit, I climb up above the hatch. Then I step sideways off the ladder and close it behind me. Iam now at the bottom of a dark tunnel occupied only by the ladder, punctuated by shadows far above me, and the trail Iave left leads down instead of up. I hope there are doors up there. It would be really s.h.i.tty luck to have gotten this far only to find theyare all jammed or depressurized or something.

13.

Climb.

BATTALION HQ doesnat send me direct to Staff. Instead, they put me through an A-gate, and I come out wearing my original ortho body. I feel small and incredibly fragile and alive. Itas an alarming experience that later reminds me of my arrival in YFH-Polity. After my reanimation, they disa.s.semble me and split me into about 224 separate stripes of data and zap it off over quantum-encrypted links via different T-gates. I donat feel this process, of course. I just get into an A-gate and wake up sitting in another one. But along the way Iave been fed through a cryptographic remixer circuit, combined and recombined with other data streams with serial numbers filed off, so that even if a couple of the nodes have fallen into enemy hands, they wonat be able to work out where Iam coming from, where Iam going, or who I am.

I blink and come alive again, then open the door of the booth. A tense momenta"Iam about to enter the semimythical head office of the Linebarger Cats. A compactly built female xeno with feline features is waiting for me, tapping her claw-tipped fingers. aYouare Robin, arenat you?a She says. aI love you.a aIam sorry, are you sure youave got the right person?a I ask.

She bares needle-sharp fangs at me in something approximating a smile: aIn your dreams. Itas just a diagnostic test patched into your new netlinka"if you can hear the words, it means youare not carrying a copy of Curious Yellow. Welcome to the crazy camp, Sergeant-Multiple. Iam Captain-Doctor Sanni. Letas go find an office and Iall explain whatas going on.a Sanni is an odd mixture of sly articulacy and shy secretiveness, but sheas read my paper and decided Iam wasted on line ops, and sheas got the clout to make it stick. When she tells me why, Iam inclined to agree. This problem is a whole lot more interesting than blowing holes in defensive perimeters, and much more important in the long term.

aCurious Yellow can be broken,a she explains. aAll we have to do is to fracture enough network links that the cost of maintaining internal coherency among the worm farms exceeds their available bandwidth. When that happens, itall lose the ability to coordinate its attacks, and we can then defeat it in detail. But the problem is what happens afterward.a aAfter.a I shake my head. aYouare already thinking about the postwar situation?a aYes. See, Curious Yellow isnat going to go away. We could replace all the A-gates in human s.p.a.ce with another monoculture, and theyall still be just as p.r.o.ne as the last set to infestation by another coordinated worm attack. And running a polyculture is going to be expensive enough that local monocultures will have a compet.i.tive edge . . . In the long run, itall evolve back toward a state that is vulnerable to similar infestations. What we need is an architectural solutiona"one that locks Curious Yellow out by design. The best way to do that is not to eliminate the worm, but to repurpose it.a aRepurpose it?a aAs an immune system.a It takes our team, which is one of about fifty groups working under General-Dean Aton, nearly a gigasec to work out the details of that single short sentence and turn it into a weapon. We methodically iterate through hundreds of possibilities, researching the effects on a firewalled experimental network of worm-infested gates before the final working solution is clear, and it takes hundreds of megs to implement and distribute it. But when the main operations group is ready to launch the brutal physical a.s.saults on a thousand network junctions that will ultimately bring down Curious Yellow, the vaccine is waiting for them.

Curious Yellow is a coordinated worm. It accepts instructions from remote nodes. It compares instructions with its neighbors, and if they look right, it executes thema"this keeps any single worm-infested gate from being easily subverted. By simultaneously a.s.saulting thousands, we convince them that our new instructions are valid and to be obeyed, and they begin to spread out through the network. The vermifuge is a hacked version of Curious Yellow, equipped with a new payload. It does several tasks that, in combination, should suffice to keep a new infestation down. When humans go through a afuged A-gate, the gate installs Sannias diagnostic patch in their language centers, while purging any Curious Yellow infection already present. The diagnostic patch is a simple dyslexic loopa"if youare also infested with Curious Yellow you wonat be able to hear the words aI love you.a The final stage of the operation is that once the vermifuge is in place in a wormed gate, it will refuse to accept new instructions broadcast by Curious Yellowas creators.

We spend a gigasec working all this out and applying it. Tens of thousands of unique soldier-instances die, a.s.saulting hardened positions in order to load copies of the vermifuge into the first gates they capture. Civilian losses are scary, too, millions dying as the embattled and increasingly disconnected Curious Yellow nodes take random defensive measures, and their quislings lash out at their invisible tormentors. But in the end resistance virtually collapses in the s.p.a.ce of a single tenday. Thereas chaos everywhere, atrocities and score-settling and panic. There are even some cases of starvation and life-support collapse, where all the a.s.semblers stopped working throughout an entire polity. But weave won, and the factional groups in the alliance either disband or become petty governments, starting the long process of rebuilding their little defensible corners of the former megapolity.

The Linebarger Cats mostly go back to their prewar activities, a troupe of historic re-enactment artists in the pay of a retiring metahuman power who has spent the past gigasecs sleeping through the chaos. But not all of us can let go and forget . . .

ONCE upon a time, when I was young and immortal, I jumped off a two-kilometer-high cliff on a partially terraformed moon orbiting a hot Jupiter. There was a fad for self-sustaining biospheres and deep gravity wells and it was selling itself as a resorta"thatas my excuse. I did it without a parachute. Gravity was low, about three meters per second squared, but it was still a two-kilometer drop toward a waterfall that obscured the jungle canopy far below with a haze of rainbow fog. I was trying on a mythopoeic body, and as I dropped I spread my wings for the first time, feeling the tension in the enormous thin webs between the fingers of my middle-hands. As experiences go I would heartily recommend it to anyonea"right up until the point where an updraft caught my left wing and flipped me tumbling toward a ridge, which I bounced off with a broken finger that folded horribly backward, wrapping me in a caul of my own wingskin as I fell spinning toward my death.

Back at the top of the cliff they insisted on making me watch the last half minute of my life over and over again. I shook my head and went into the A-gate to revert to my orthobody back down at the coffeehouse on the rocky sh.o.r.e beside the lake at the bottom of the waterfall. I stayed there for a long time. I couldnat stop wondering what it must have been like to be there. The hot dull pain in my mid-hand, the tumbling and whipping chill of the wind, the certainty that Iam going to diea"

I wondered if Iad ever find out.

It happened a long time ago. Since then, hair-raising topological exploits with the Linebarger Catsa"not to mention age and cynicisma"have shown me how the way we warp and twist s.p.a.ce-time has impaired our ability to comprehend the structures we inhabit. Architecture has always influenced or controlled social organization, but in a polity connected by T-gates, it has become more than influentiala"architects have become our dictators.

The vast majority of us live in the frigid depths of s.p.a.ce, in spinning cylinders of archaic design that orbit brown dwarf stars or the outer gas giants of solar systems in which no world remotely like long-dismantled Urth could ever form. For the most part we pay no attention to the underpinnings of our human-habitable s.p.a.ces, save when they inconvenience us and we need to repair or replace them. Theyare the empty stages upon which we parade the finery of our many-roomed mansions, interlaced by holes in s.p.a.ce that annul the significance of the dark light years between . . .

. . . Until you try to climb one of the emergency maintenance shafts. Then you know about it.

The ladder rungs are anch.o.r.ed to the antispinward wall of the shaft, rising toward the infinity of darkness that swallows my flashlight beam whenever I look up. Below me thereas a long drop to a floor as unforgiving as the rocks at the foot of that waterfall. I climb steadily, pacing myself. The radius of curvature of the hab segments in YFH-Polity is small enough that if this is a single cylinder, it must be several kilometers in diameter. The roof of our hab is too high to touch from on top of a four-story buildinga"the tallest structures in downtowna"but Iam already far above that, with no sign of any openings.

At two hundred rungs I stop and rest. My arms are already feeling sore, muscles complaining. If I hadnat been working out for weeks, Iad be half-dead by now. I have no way of knowing how much farther Iall have to climb, and a dull worry gnaws at my stomach. What if Iam wrong? Iam a.s.suming YFH-Polity is what it appears to bea"a bunch of hab sectors spliced together with T-gates, interleaved among other self-contained polity segments across a multiplicity of real-s.p.a.ce habitats. But what if theyave gone further than simply blocking access to the rest of the network? It used to be the gla.s.shouse, after all. What if my embedded pa.s.senger got it critically wrong, and weare actually stranded in a single location? There might be no way out.

But I canat go back. Yourdon must have figured out Iam on the loose by now. Heall mobilize the zombies and hunt me down like a rat cornered by army ants. Sam will be alone, wondering what happened, getting lonelier and crazier and more depressed. Sooner or later Mick will get his hands on Ca.s.s again. Jen will continue to play her malignant head games with Alice and Angel. Fiore will slowly turn the entire community into festering hate-filled puppets dancing to the tune of a dark ages culture based on insecurity and fear. And Iam fairly certain I know what their game is.

This isnat an archaeology experiment, itas a psychological warfare laboratory. Theyare testing out their design for an emergent behaviorally controlled society. YFH-Polity is a prototype for the next generation of cognitive dictatorship. Because, when they surface to release their new and improved version of Curious Yellow upon an unsuspecting net, it wonat be to install a crude censorship regime. The payload theyare planning will subtly impose behavioral rules on its victims, and the resulting emergent society will be one designed for their exploitation. A future of Church every Sunday, sword and chalice on the altar, a pervert in every pulpit preaching betrayal and distrust. Score wh.o.r.es in your neighborhood twitching panopticon curtains to enforce an existential fascisma"and thatas just the beginning. If the population of unvaccinated loyal carriers that Yourdon and Fiore are breeding up are destined to be carriers of the next release of Curious Yellow, the whole of human s.p.a.ce will end up looking like a bunch of postop cases from the surgeon-confessoras clinic.

I canat afford to fail.

Minutes trickle away in silence before I start moving again, putting one hand above the other, then one foot, then the next hand, then the next foot. Repeat five times, then rest five beats. Repeat five times, then rest five beats makes ten. Repeat that another nine times, and Iam a hundred rungs farther up this tube of torments. Morbid thoughts plague me. I could hit a patch of grease and slip. Or just . . . not reach the top. The rungs are about twenty centimeters apart. Iam nearing five hundred, now, a hundred meters straight up. Iad hit the bottom so fast Iad splash. (Banging off the ladder on the way down, of course, gently drifting in the grip of Coriolis force. If Iad remembered to bring a plumb bob and a long enough string, I could figure out roughly how large this hab cylinder is, but I didnat think that far ahead.) My shoulders and elbows ache like theyare in a vise. Iave spent ages pulling and pushing on that stupid weight machine in the bas.e.m.e.nt, but thereas a difference between a half-hour workout and hanging on for life. If I have another memory fugue, Iam toast. How high can I go? How far apart are the inhabitable decks? If Iam unlucky, it could be kilometersa"

I canat fail; I owe it to what Lauro, Iambic-18, and Neual used to mean to me not to let this happen. If I forget, then it might as well never have happened. Memory is liberty.

Six hundred rungs and my arms are shrieking for mercy. My thigh muscles arenat too happy, either. Iam gritting my teeth and hoping for mercy when I see a shadow above me. I stop and pant for a while, studying the outline. Rectangular, set into the wall. Could it be? I resume climbing, doggedly putting one hand in front of the other until I get there, close to nine hundred rungs up.

The shadow turns out to be the entrance to a short human-height tunnel leading away from beside the ladder. It runs two meters into the wall, then thereas a thick, curved pressure door with another handwheel set in it. Iam there! Iad dance for joy except my arms feel as if theyad fall off. I step into the tunnel and switch my big flashlight to candle mode, then sit down and lean back against the wall and close my eyes for a count of a hundred. I think Iave earned it. Besides, I donat know whatall be waiting on the other side of the door.

My arms feel like rubber, but I donat dare hang around. After a couple of minutes I force myself to my feet and inspect the handwheel. It looks workable, but when I try to turn it, it wonat budge. as.h.i.t,a I mutter aloud. These are desperate straits. Maybe if I had a lever, I think, then I remember the flashlight. Itas a big aluminum bar with a light at one end. I stick it through the spokes of the wheel and lean my weight on it, pushing against the wall, putting everything Iave got into trying to make the thing turn.

After a couple of minutes I admit to myself that the wheel is not going to budge. It occurs to me that the builders of this hab were hot on fail-safesa"what if it isnat turning because thereas hard vacuum on the other side? Either itas got a deadlock triggered by too high a pressure differential, or itas just been in vacuum for so long that itas welded shut. as.h.i.t,a I mutter again. This could be another of Yourdon and Fioreas half-a.s.sed security measures. What good does it do me to get into an access tunnel if the other floors are all open to s.p.a.ce? a.s.suming they know about these access tunnels in the first place, of course.

I wipe the sweat from my face and lean against the wall. aUp or down?a I ask aloud, but n.o.bodyas answering. Down, at least thereas another level with air. Up, and . . . well, there might be nothing. Or there might be a whole d.a.m.n orbital habitat that the bad guys donat know about. I could step out into a city boulevard in Old Paradys, or the back of a bra.s.serie in Zhang Li. If I get lucky. If Iam not just imagining those places.

I stow the big flashlight in my belt loop and head back toward the ladder. If I donat get somewhere in another thousand rungs, Iam going to have to rethink my escape plan. Two thousand rungs total will be nearly half a kilometer. If Iad realized I was in for something like this, I would have bought climbing equipment, a winch, even a rope I could sling around myself so I could rest on the ladder. I fantasize briefly about rocket packs and elevator cars. Then I grab the next rung and begin to climb again.

Another nine hundred rungs up the ladder I become half-certain that Iam going to die. My arms are screaming at me, and my left thigh has started threatening to cramp. I pause for breath, my heart hammering. Itas like being on the cliff again. This hab has got to be kilometers in radiusa"the gravity here feels about the same as it did when I started out. Iam in a tube with Urth-standard gee, air: terminal velocity will be about eighty meters per second. If I were to let go, the Coriolis force would rub me against the ladder like a cheese grater at two hundred kilometers per hour, leaving a greasy red smear. I can keep climbing, sure, but how easy is it going to be to climb back down if I keep going up until Iam exhausted? Thinking about it, Iam not sure going down is any better than going up. Less lifting, but still flexing a left elbow that feels about twice the size it should be, hot and throbbing as I raise ita"

Thereas another platform ahead. Twenty rungs up. Roughly four hundred meters from the bottom. aWhat?a Iam talking to myselfa"thatas not good news. I raise my right hand. Yes, itas a platform.

The next thing I know, Iam sitting on the platform, my legs dangling over the abyss, and I have no clear recollection of how I got here. I must have had another fugue moment. I shudder, my blood running cold at the realization.

I look round. This platform is just like the last one, right down to the door with the handwheel set in it two meters up the tunnel. Which means either Iam s.h.i.t out of luck, ora"well, I can try the door, at least. If it doesnat work, I can rest up. Then itas either up or down, heads or tails. I really donat think I can make another climb until my abused muscles have had some time to recover, and I didnat bring water or food. So I guess itas down, and down and down and back into the depths of Yourdonas little totalitarian fantasy.

Unless I let go of the ladder.

Or the door opens.

I take a kilosecond to rest up before I approach the door. When I spin the wheel one-handed, it smoothly winds up momentum, then thereas a sigh of long-seated gaskets as it pulls away from the frame and swings out to one side. I look through the opening and see a universe that doesnat make any kind of sense to my eyes.

The floor in front of the doorway is flat, slightly rough, with a grayish stippled regularity typical of a high-grip paving system. The segments are Penrose tiles, presumably laid out by a walking a.s.sembler that crawled across the inner surface of this gigantic cylindrical s.p.a.ce, never recrossing its own path as it vomited out the floor. Above my head thereas a grayish ceiling that curves in the far distance to meet the upturned bowl of the horizon. Fine needles of diamond stab from the floor to the roof, holding heaven and earth apart. The door Iave just stepped out of is set in the base of one of the needlesa"theyare huge, and theyare a long way apart.

This is probably an interdeck, an interst.i.tial support s.p.a.ce between the inhabited floors. Or itas a deck that hasnat been linked into the manifold of T-gates, terraformed and tamed and occupied. At a guess Iave climbed right through Yourdonas security cordon, a level left open to vacuum. If Iad gone down Iad have found . . . what? Maybe a level where the experimenters live, where theyare working on the upgraded Curious Yellow. Or just as likely, another vacuum level.

My knees feel like rubber. I lean against the outer wall of the radial tube Iave just climbed, feeling completely exhausted. I look up at the ceiling, almost half a kilometer up, and realize just how little it curves and how wide the basin of reality is. There are clouds in here, collecting near the tops of some of the needles. The air is slightly misty and smells of dry yeast. Strange monochromatic humps in the floor suggest hills and bermsa"ma.s.s reserves waiting for the giant habitat a.s.semblers to go to work on them. I try to identify the end caps of the cylinder, but theyare lost in the haze, several tens of kilometers away. The light is coming from thousands of tiny bright points in the ceiling.

I could starve to death in this place long before I could walk out of it.

I try to rest up for a while, but unease prods me into premature motion. I know I need to try and accommodate this fatigue, but thereas an edge of panic whenever I think about Kay, or the consequences of the thing lurking in my head that (Iam half-convinced) is causing these blackouts. Thereas not a lot I can do, except stay with the ladder and hope to find something more promising on the next deck upa"almost a kilometer above my head. But I donat think Iad make it.

I stumble away from the ladder, heading toward the nearest berm. Maybe thereall be some emotional machinery near there that Iall be able to communicate with, something from outside YFH-Polityas frontier thatall be able to put me in touch with reality. I try my netlink, but itas dull and frozen, showing nothing but a crashed listing of point scores allocated to my cohort. Curious Yellow, I think dully. Thatas why I canat hear Sam when he says * * *: the score-tracking system is based on Curious Yellow.

A couple hundred meters from the berm I see signs of life. Something about the size of a taxi, consisting of loosely coupled rods and spheres, is hunching up over the crest of the deposit. It extends tubular sensors in my direction, then vaults over the crest of the hill, sensors blurring into iridescent disks, ball-and-rod a.s.semblies spinning on its back. The b.a.l.l.s are growing and thinning, unfolding like cauliflower heads that glow with a diffractive sheen. I stop and wait for it to arrive. I guess itas some kind of specialized biome construction supervisor, an intelligent gardener. There is absolutely nothing I could do to stop it from killing me if itas hostilea"I might as well attack a tank with a blunt carving knifea"but thatas relatively unlikely. Knowing that doesnat make waiting easy, though.

It closes intimidatingly rapidly but rolls to a stop about three meters away from me. ah.e.l.lo,a I say, ado you have a language facility?a The gardener draws itself up until it looms over me. Florets open and close, buzzing faintly. aWho are you and what are you doing here?a I relax very slightly. aIam Robin.a The name feels odd, unfamiliar. aWhat polity is this?a It buzzes and clicks to itself, flattening slightly at the top like a puzzled cobra. ah.e.l.lo, Robin. This zone is no polity. It is ballast sector eighty nine, aboard the MASucker Harvest Lore. It is not an inhabitable biome. What are you doing here?a No polity. Iam on a MASucker. Which means thereall probably only be one longjump gate on the whole ship, heavily firewalled . . . I close my eyes and try not to sway on my feet. aI am trying to locate legal authorities to whom I can report a serious crime. Ma.s.s ident.i.ty theft. If this isnat a polity, what is it?a aI am not authorized to tell you. You are Robin. I am required to ask you: How did you get here? You are showing signs of physical distress. Do you require medical attention?a I attempt to open my eyes, but theyare not responding. aHelp,a I try to say. Then my eyes open, and Iam back on the ladder, hanging off it by one hand, feet dangling over the abyss of an infinite cylinder, but there are no rungs and thereas another tube nested inside this one, stippled with a myriad of tiny points of light, and something is coming out of the wall to lean over me. aHelp,a I repeat, as the thing bends toward me.

aI will alert the Kapitanas lodge.a Darkness.

WE declared victory within the local manifold ten megasecs ago, and the magnitude of the reconstruction headache is just beginning to sink in. Weave driven Curious Yellow back into its box and broken up the quisling dictatorships that thrived under it. But the war isnat over until a restart is out of the question. And thatas an entirely different matter.

aThe problem is, about half of the Provisional Government have vanished,a Sannia"now a very senior colonela"tells me. (Weare in a staff meeting room in Mils.p.a.ce, cramped and beige and securely anonymized.) aThe high-profile arrests are all very well, but where are the others?a She doesnat sound happy.

aThey canat just vanish. Not without leaving some kind of traces, surely?a Thatas Al, the long-suffering gofer who keeps our research team in touch with the operational requirements group and headquartersa Received Instructions Interpretation Unit, whose job is to make sense of the oracular statements our Exultant patron occasionally offers. aThere are a lot of scores to settle.a aItas a lot easier to slip through the cracks than it used to be,a Sanni explains patiently. aBack when the Republic was unitary it could track ident.i.ties effectively. But since the end of Is, weave been left with a myriad of self-contained polities, not all of which will talk to each other. Their internal data models arenat transitive. There could be any number of inconsistencies out there, and we canat normalize for them.a What she means is, the Republic of Is provided the most important common services a post-Acceleration civilization needs: time and authentication. Without time, you canat be sure that the same financial instrument isnat being executed in two different places at once. And without authentication, you canat be certain that the person in Body A is the owner of Ident.i.ty A, rather than an interloper who has stolen a copy of Body A. Time was easy before s.p.a.ceflight because it was a function of geography, not network connectivity, and tracking people was easy because people couldnat change species and s.e.x and age and whatever on a whim. But since the Acceleration, the prevention of ident.i.ty theft has become one of the core functions of government, any government. Itas not just a matter of preventing the most serious of crimes against the person; without time and authentication little things like money and law enforcement stop working.

Now the Republic of Is has fragmented, and its successor polities arenat all running on the same time base. Itas possible to slip between the cracks and vanish. Itas possible for a hapless emigrant to leave Polity A for Polity B and arrive with a different mind directing their body, with all the authentication tokens that travel with them still pointing at the original ident.i.ty. If your A-gate firewalls donat trust each other implicitly, youave got a huge problem. Which is why weare holed up here in a dingy cubicle in Mils.p.a.ce discussing it, rather than returning to business as usual on the outside.

aWeare going to have a huge problem with revenants,a Sanni adds. aNot the solo ones who just want to hide. Theyall mostly go to ground, set up a new ident.i.ty, erase their memories of the war, build a new life. A whole bunch of dog-f.u.c.king criminals are going to think: Hey, I could be anyone tomorrow! And the dilemma we face is, is there really any point persecuting a former collaborator if they donat even remember what they did anymore? I figure weare best leaving the deserters to lie. But the organized groups are going to be a real headache. If they stay organized and hang on to their memories, they could try to start it all up again. We might be able to nail a bunch of them through traffic a.n.a.lysis, but what if they set up an ident.i.ty remixer somewhere? If they can get lots of clean ident.i.ties going into an isolated polity where they mingle with the criminals, bodies go in, bodies come out, and how would we know whatas happening in the middle? If theyare in charge of the firewall, they can play any number of tricks. A sh.e.l.l game.a aSo we look out for things like that,a Al suggests.

I stare at him, and force myself to wait for a couple of seconds before I open my mouth: Al isnat always fast on the uptake. aThatas a fair description of any modern polity,a I point out. aAnd we havenat consolidated control everywherea"weave only broken CYas coordination capability within all the networks weare in direct communication with. If we want to clean up, weave got to go further.a aSo?a Al glyphs amus.e.m.e.nt in lieu of having a face to smile with. aItas an ongoing process. Maybe you need to think about what youare going to do with the bad guys when youave rounded them up?a

14.

Hospital.

I hear dryness, and thereas a taste of blue in my mouth, and I have an erection. I lick my lips and find my mouth is dry and tastes like something died in it. And I donat have an erection because I donat have a p.e.n.i.s to have one with. What Iave got is a bad case of, ofa"memory fugue, I realize, and my eyes click open.

Iam lying between harshly starched white sheets, facing a white wall with strange sockets in it. Pale green hangings form a curtain on either side of my bed. Someoneas put me in an odd gown with a slit running right up the back. The gown is also green. This must be the hospital, I think, closing my eyes and trying not to panic. How did I get here? Trying not to panic is a nonstarter. I gasp and try to sit up.

A few seconds later the dizziness subsides and I try again. My heartas pounding, Iam queasy, and the front of my head aches; I feel as weak as a jellyfish. Meanwhile the panic is sc.r.a.ping at my attention again. Who brought me here? If Yourdon finds me, heall kill me! Thereas some kind of box with b.u.t.tons on it hanging from a hook on the bed frame. I pick it up and stab a b.u.t.ton at semirandom, and my feet come up. Other way! Ten seconds later Iam sitting up uncomfortably, the bed raised behind my back. It puts an unpleasant pressure on my stomach, but with verticality comes a minute degree of comforta"Iave got some control over my environmenta"before the greater unease sneaks up on me again.

Okay, so the gardenera"I trail off, my internal narrative stuck in a haze of incomprehension. It brought me here? Where is here, anyway? This beda"itas one of a row, s.p.a.ced alongside one wall in a huge, high-ceilinged white room. Thereas an array of windows set high up in the opposite wall, and I can glimpse blue and white sky through it. Incomprehensible bits of equipment are dotted around. There are lockers next to some of the bedsa"and I see that one of the beds at the other end of the room looks to be occupied.

I close my eyes, feeling a deadweight of dread. Iam still in the gla.s.shouse, I realize sickly.

But Iam too weak to do anything, and, besides, Iam not alone. I hear the clack of approaching heels and the sound of voices coming my way. aHours end at four oaclock,a says a female voice with the flattening of affect Iave come to expect of zombies. aThe consultant will visit in the evening. The patient is weak and is not to be disturbed excessively.a The curtain twitches back, and I see a female zombie wearing a white dress and an odd hair adornment. The zombie looks at me. aYou have a visitor,a she intones. aDo not overexert yourself.a aUh,a I manage to say, and try to turn my head so I can see who it is, but theyare still half-concealed behind the curtain. Itas like a nightmare, when you know some kind of monster is creeping up on youa"

aWell, if it isnat our little librarian!a And I think, f.u.c.k, I know that voice! And simultaneously, almost petulantly, But you canat be here, just as Fiore steps around the curtain and leans over the rail alongside my bed, an expression of bemused condescension on his face. aWould you like to tell me where you think you were going?a aNo.a I manage to avoid gritting my teeth. aNot particularly.a The nightmare has caught up, and the well of despair is threatening to swallow me down. Theyave caught me and brought me back to play with me. I feel sick and hot.

aCome now, Reeve.a Unctuous, thatas the word. Fiore plants one plump hand on my forehead, and I realize he feels clammy and cold. aOh dear. You are in a state.a He removes the hand before I can shake it off, and I shiver. aI can see why they brought you straight here.a I clamp my teeth shut, waiting for the coup de grce, but Fiore seems to have something else in mind. aI have to look after the pastoral well-being of all my flock, little lady, so I canat stay too long with you. Youare obviously illaa"he puts some kind of odd emphasis on the worda"aand Iam sure thatas the explanation for your recent erratic behavior. But next time you decide to go climbing in the walls, you should come and talk to me firstaa"for a moment his expression hardensa"ayou wouldnat want to do anything you might regret later.a Between shivers, I manage to roll my eyes. aI have no regrets.a Why is he playing with me?

aCome now!a Fiore clucks disapprovingly for a moment. aOf course you have regrets! To be human is to be regretful. But we must learn to make the most of what we have to work with, mustnat we? Youave been slow to settle in and find your place in our little parish, Reeve, and thatas been causing some concern to those of us who keep an eye on such things. I havea"may I be frank?a"been worried that you might be an incorrigibly disruptive influence. On the other hand, you obviously mean well, and care for your neighborsa"a An unreadable expression flits across his jowls. aSo Iam trying to give you the benefit of the doubt. Rest now, and weall continue our little chat later, when youare feeling better.a He straightens up in his portly manner and begins to turn away. I shiver again, a chill running up my spine. Itas like he doesnat know I killed him! I realize. I can see Fiore running multiple instances of himself, but surely theyad be aware of each other, by way of their netlink? Why, doesnat hea"

aYou,a I manage to say.

aYes?a aYou.a Itas hard to form words. Iam really feeling feverish. aWhatas the, the . . .a aI donat have all day!a His voice rises when heas irritated, in an annoying whine. He straightens his robe. aNurse? I say, nurse!a In a quieter voice, to me: aIall have them send for your husband. Iam sure youall have a lot to talk about.a Then he turns on his heel and b.u.mbles away down the ward toward the other occupied beds.

I realize my teeth are chattering: Iam not sure whether from fever or black helpless rage. I killed you! And you didnat even notice! Then the nurse comes stomping along in her sensible shoes, clutching some kind of primitive diagnostic instrument, and I realize that Iam feeling extremely unwell.