Charles Stross - The Atrocity Archives

Roughly one in a thousand carbon nuclei in the body that used to belong to Chaitin spontaneously acquire an extra eight protons and seven or eight neutrons. The mass deficit is bad enough-there's about as much energy coming out of nowhere as a small nuke would put out-but I'll leave that to the cosmologists. What's bad is that each of those nuclei is missing a whopping eight electrons, so it forms a wildly unstable carbosilicate intermediary that promptly grabs a shitload of charge out of the nearest electron donor molecules. Then it destabilizes for real, but in the process it's set off a cascade of tiny little acid/base reactions throughout the surrounding hot chemical soup that used to be a human body. Chaitin's body turns red, the kind of dull red of an electric heating element-then it steams , bits of his kit melting as his skin turns black and splits open. He begins to topple toward me and I yell and jump away. When he hits the ground he shatters, like a statue made of hot glass.

The next thing I know I'm on my knees on the frozen ground, breathing deeply and trying desperately to tell my stomach to be still. I can't afford to throw up because if I vomit in my face mask I will die, and then I won't be able to tell Alan what kind of mistake he'll be making if he sets off the demolition charge.

This whole world has been turned into a mousetrap: a body-snatching demon, patient and prepared, waiting for us little furry folk with beady black eyes to stick our curious noses inside.

I pick myself up, watching the steamy vapour pour from the ground around the molten depressions my kneepads melted in the permafrost as I take more deep, laborious breaths. Static ebbs and flows in my ears like bacon frying, the distorted sidebands of a transmission counting down the minutes to the artificial sunrise. I try not to look at what's left of Chaitin.

They summoned an infovore: something that eats energy and minds. A thing-I don't know what sort-from a dead cosmos, one where the stars had long since guttered into darkness and evaporated on a cold wind of decaying protons, the black holes dwindling into superstring-sized knots on a gust of Hawking radiation. A vast, ancient, slow thinker that wanted access to the hot core of a youthful universe, one mere billions of years from the Big Bang, poised for a hundred trillion years of profligate star-burning before the long slide into the abyss.

On my feet now, I check my air supply: good for two and a quarter hours. That will see me through-the bomb's going to blow in just over an hour. I look round, trying to work out which way to go. Thoughts are clamouring in my head, divergent priorities-

The thing was hungry. First it did what it was invited to do, sucked the minds and life from the Ahnenerbe's enemies, occupied their bodies, and learned how to pass for human. Then it pulled more of itself through the gate than they'd expected. It's big-far too big to fit through a man-sized gate-but it had access to all the energy it wanted, and all the minds to sacrifice, more than enough power to force it wide open and squirm through into this new, rich cosmos.

The monster they summoned gave the Ahnenerbe more than they asked for. As well as damping the fusion phoenix at the heart of every star, it started to drain energy directly out of spacetime, messing with the Planck constant, feeding on the false vacuum of space itself. Light stretched, grew redder; the gravitational constant became a variable, dropping like a barometer before a storm. Fusion processes in the sun guttered and died, neutrons and protons remaining stubbornly monogamous. The solar neutrino flux disappeared first, though it would take centuries for the sun itself to show signs of cooling, for the radiation-impeded gravitational collapse to a white dwarf core to resume. Meanwhile, the universe began to expand again, prematurely ageing by aeons in a matter of years.

Back to the here-and-now. Here I am with a corpse. And a gun. And the corpse manifestly killed using the gun in my hands. Shit. I twiddle the squelch on my radio but get nothing but loud hissing and incoherent bursts of static. What am I going to tell Alan-"Look, I know I appear to have shot one of your men, but you've got to abort the mission"?

I glance up at the sky. It's night, but maybe the sun would be visible if I knew where to look. Visible-and shrunken, farther away than it is back home, for as the creature sucks energy out of spacetime, space itself is getting bigger, and emptier. Losing energy. Find Alan. Stop the bomb. Get everybody out fast. It took a lot of energy for the thing to fully open the gate to its original home and bring itself through to this shattered Earth; energy that is no longer available in this drained husk of a universe, energy that it needs if it's to move on to pastures new. About all it's capable of on its own right now was to listen for an invitation-from the terror cell in Santa Cruz-and answer their call. What will it do if we dump more energy into it? Open a gate back to its original home? Expand the gate to our Earth? There's a worst-possible-case scenario here that I don't even want to think about-I'm going to have nightmares about it for years, if I have any years ahead of me to have nightmares in.

Having dragged its huge, cold presence through to squat in the ruins of the victorious Reich, it settled down to wait: patient, for it has waited for an infinity of infinities already, waiting for a hot, fast thinker to open the gate to the next universe. Focussed in one place, it will be able to move far faster this time-no need for a sacrifice of millions to get its attention. Once invited-by the clever stupidity of a terrorist cell, perhaps-it can take possession of a body and, using what it has learned of the nature of humanity from the Ahnenerbe-SS, manipulate those around it. The possessed, its agent on the other side of that first gate, must arrange to open a connection, then find an energy source to crack it wide open, big enough to admit the rest of the eater. Opening a gate wide enough for a human body, with an agent at both ends, would take about as much energy as it had left-the lives of all the remaining Ahnenerbe-SS survivors in this world, hoarded against such an eventual need. But to open a gate so that it can admit an ice giant-a being big enough to carve monuments on the moon and suck dry a universe-will take much more energy: energy gained from either a major act of necromancy or a singularly powerful local source.

I look around. I'm at the foot of a hill; on the other side of it there's a wall, and a couple of pathetic corpses, and half a platoon of SAS specialists. Behind me there's a petrified forest and a castle of shadows, populated with nightmares. (Oh, and a hydrogen bomb that's going to go off in about seventy minutes.) Where is everybody? Strung out between the castle and the gate, that's where.

Got to tell Alan not to set off the bomb. I pick up my sack of hands and stagger downhill toward the skeletal trees, feet and ankles tensed with that walking on glass sensation you get when you're afraid there's nothing but black ice underfoot, one hand clutching the basilisk gun at arm's reach. Branches claw at me in the twilight, making me flinch inside my helmet; they snap and tinkle against my visor, rigid bundles of mummified twigs with all the heat sucked out of them. If there's more than one of the body snatchers here …

I skid and go down on one thigh, hard. Something crunches underfoot, like twigs snapping. I lever myself upright, rub my leg and wince, breath loud in my ears. Looking down I see a hump of frozen brown, a small rabbit or a rat or something else that's been dead for years. Dead. I stoop and pick up my bag of severed hands, tagged for identification at a later date. Wouldn't this be a good time to think about precautions? In case there are other demons stalking this frozen plain in stolen bodies?