I suppose that I could claim that I had always suspected that the world was a cheap and shoddy sham, a bad cover for something deeper and weirder and infinitely more strange, and that, in some way, I already knew the truth. But I think that's just how the world has always been. And even now that I know the truth, as you will, my love, if you're reading this, the world still seems cheap and shoddy. Different world, different shoddy, but that's how it feels.

They say, here's the truth, and I say, is that all there is? And they say, kind of. Pretty much. As far as we know.

So. It was 1977, and the nearest I had come to computers was I'd recently bought a big, expensive calculator, and then I'd lost the manual that came with it, so I didn't know what it did any more. I'd add, subtract, multiply and divide, and was grateful I had no need to cos, sine or find tangents or graph functions or whatever else the gizmo did, because, having been turned down by the RAF, I was working as a bookkeeper for a small discount carpet warehouse in Edgware, in North London, near the top of the Northern Line, and I was sitting at the table at the back of the warehouse that served me as a desk when the world began to melt and drip away.

Honest. It was like the walls and the ceiling and the rolls of carpet and the News of the World Topless Calendar were all made of wax, and they started to ooze and run, to flow together and to drip. I could see the houses and the sky and the clouds and the road behind them, and then that dripped and flowed away, and behind that was blackness.

I was standing in the puddle of the world, a weird, brightly coloured thing that oozed and brimmed and didn't cover the tops of my brown leather shoes (I have feet like shoeboxes. Boots have to be specially made for me. Costs me a fortune). The puddle cast a weird light upwards.

In fiction, I think I would have refused to believe it was happening, wonder if I'd been drugged or if I was dreaming. In reality, hell, it had happened, and I stared up into the darkness, and then, when nothing happened, I began to walk, splashing through the liquid world, calling out, seeing if anyone was there.

Something flickered in front of me.

"Hey," said a voice. The accent was American, although the intonation was odd.

"Hello," I said.

The flickering continued for a few moments, and then resolved itself into a smartly-dressed man in thick horn-rimmed spectacles.

"You're a pretty big guy," he said. "You know that?"

Of course I knew that. I was 19 years old and I was close to seven feet tall. I have fingers like bananas. I scare children. I'm unlikely to see my 40th birthday: people like me die young.

"What's going on?" I asked. "Do you know?"

"Enemy missile took out a central processing unit," he said. "Two hundred thousand people, hooked up in parallel, blown to dead meat. We've got a mirror going of course, and we'll have it all up and running again in no time flat. You're just free-floating here for a couple of nanoseconds, while we get London processing again."

"Are you God?" I asked. Nothing he had said had made any sense to me.

"Yes. No. Not really," he said. "Not as you mean it, anyway."

And then the world lurched and I found myself coming to work again that morning, poured myself a cup of tea, had the longest, strangest bout of deja vu I've ever had. Twenty minutes, where I knew everything that anyone was going to do or say. And then it went, and time passed properly once more, every second following every other second just like they're meant to.

And the hours passed, and the days, and the years.
e
I lost my job in the carpet company, and got a new one bookkeeping for a company selling business machines, and I got married to a girl called Sandra I met at the swimming baths and we had a couple of kids, both normal sized, and I thought I had the sort of marriage that could survive anything, but I hadn't, so she went away and she took the kiddies with her. I was in my late 20s, and it was 1986, and I got a job on Tottenham Court Road selling computers, and I turned out to be good at it.

I liked computers.

I liked the way they worked. It was an exciting time. I remember our first shipment of ATs, some of them with 40 megabyte hard drives... Well, I was impressed easily back then.

I still lived in Edgware, commuted to work on the Northern Line. I was on the tube one evening, going home - we'd just gone through Euston and half the passengers had got off -- looking at the other people in the carriage over the top of the Evening Standard and wondering who they were - who they really were, inside - the thin, black girl writing earnestly in her notebook, the little old lady with the green velvet hat on, the girl with the dog, the bearded man with the turban...

And then the tube stopped, in the tunnel.

That was what I thought happened, anyway: I thought the tube had stopped. Everything went very quiet.

And then we went through Euston, and half the passengers got off.

And then we went through Euston, and half the passengers got off. And I was looking at the other passengers and wondering who they really were inside when the train stopped in the tunnel. And everything went very quiet.

And then everything lurched so hard I thought we'd been hit by another train.

And then we went through Euston, and half the passengers got off, and then the train stopped in the tunnel, and then everything went -

(Normal service will be resumed as possible, whispered a voice in the back of my head.)

And this time as the train slowed and began to approach Euston I wondered if I was going crazy: I felt like I was jerking back and forth on a video loop. I knew it was happening, but there was nothing I could do to change anything, nothing I could do to break out of it.

The black girl, sitting next to me, passed me a note. ARE WE DEAD? it said.

I shrugged. I didn't know. It seemed as good an explanation as any.

And then everything faded to white.

There was no ground beneath my feet, nothing above me, no sense of distance, no sense of time. I was in a white place. And I was not alone.

The man wore thick horn-rimmed spectacles, and a suit that looked like it might have been Armani. "You again?" he said. "The big guy. I just spoke to you."

"I don't think so," I said.

"Half an hour ago. When the missiles hit."

"Back in the carpet factory? That was years ago."

"About thirty-seven minutes back. We've been running in an accelerated mode since then, trying to patch and cover, while we've been processing potential solutions."

"Who sent the missiles?" I asked. "The U.S.S.R.? The Iranians?"

"Aliens," he said.

"You're kidding?"

"Not as far as we can tell. We've been sending out seed-probes for a couple of hundred years now. Looks like something has followed one back. We learned about it when the first missiles landed. It's taken us a good twenty minutes to get a retaliatory plan up and running. That's why we've been processing in overdrive. Did it seem like the last decade went pretty fast?"

"Yeah. I suppose."

"That's why. We ran it through pretty fast, trying to maintain a common reality while processing."

"So what are you going to do?"

"We're going to counter-attack. We're going to take them out. It's going to take a while: we don't have the machinery right now. We have to build it."

The white was fading now, fading into dark pinks and dull reds. I opened my eyes. For the first time.

So. Sharp the world and tangled-tubed and strange and dark and somewhere beyond belief. It made no sense. Nothing made sense. It was real, and it was a nightmare. It lasted for thirty seconds, and each cold second felt like a tiny forever.

And then we went through Euston, and half the passengers got off...

I started talking to the black girl with the notebook. Her name was Susan. Several weeks later she moved in with me.

Time rumbled and rolled. I suppose I was becoming sensitive to it. Maybe I knew what I was looking for - knew there was something to look for, even if I didn't know what it was.

I made the mistake of telling Susan some of what I believed one night - about how none of this was real. About how we were really just hanging there, plugged and wired, central processing units or just cheap memory chips for some computer the size of the world, being fed a consensual hallucination to keep us happy, to allow us to communicate and dream using the tiny fraction of our brains that they weren't using to crunch numbers and store information.

"We're memory," I told her. "That's what we are. Memory."

"You don't really believe this stuff," she told me, and her voice was trembling. "It's a story."

When we made love, she always wanted me to be rough with her, but I never dared. I didn't know my own strength, and I'm so clumsy. I didn't want to hurt her. I never wanted to hurt her, so I stopped telling her my ideas.

It didn't matter. She moved out the following weekend.

I missed her.

The moments of deja-vu were coming more frequently, now. Moments would stutter and hiccup and falter and repeat.

And then I woke up one morning and it was 1975 again, and I was sixteen, and after a day of hell at school I was walking out of school, into the RAF recruiting office next to the kebab house in Chapel Road.

"You're a big lad," said the recruiting officer. I thought he was American, but he said he was Canadian. He wore big horn-rimmed glasses.

"Yes," I said.

"And you want to fly?"

"More than anything," I said. It seemed like I half-remembered a world in which I'd forgotten that I wanted to fly planes, which seemed as strange to me as forgetting my own name.

"Well," said the horn-rimmed man, "We're going to have to bend a few rules. But we'll have you up in the air in no time." And he meant it, too.

The next few years passed really fast. It seemed like I spent all of them in planes of different kinds, cramped into tiny cockpits, in seats I barely fitted, flicking switches too small for my fingers.

I got Secret clearance, then I got Noble clearance, which leaves Secret clearance in the shade, and then I got Graceful clearance, which the Prime Minister himself doesn't have, by which time I was piloting flying saucers and other craft that moved with no visible means of support.

I started dating a girl called Sandra, and then we got married, because if we married we got to move into married quarters, which was a nice little semidetached house near Dartmoor. We never had any children: I had been warned that it was possible I might have been exposed to enough radiation to fry my gonads, and it seemed sensible not to try for kids, under the circumstances: didn't want to breed monsters.

It was 1985 when the man with horn-rimmed spectacles walked into my house.

My wife was at her mother's that week. Things had got a bit tense, and she'd moved out to buy herself some 'breathing room'. She said I was getting on her nerves. But if I was getting on anyone's nerves, I think it must have been my own. It seemed like I knew what was going to happen all the time. Not just me: it seemed like everyone knew what was going to happen. Like we were sleepwalking through our lives for the tenth or the twentieth or the hundredth time.

I wanted to tell Sandra, but somehow I knew better, knew I'd lose her if I opened my mouth. Still, I seemed to be losing her anyway. So I was sitting in the lounge watching The Tube on Channel Four and drinking a mug of tea, and feeling sorry for myself.

The man with the horn-rimmed specs walked into my house like he owned the place. He checked his watch.

"Right," he said. "Time to go. You'll be piloting something pretty close to a PL-47."

Even people with Graceful clearance weren't meant to know about PL-47s. I'd flown one a dozen times. Looked like a tea-cup, flew like something from Star Wars.

"Shouldn't I leave a note for Sandra?" I asked.

"No," he said, flatly. "Now, sit down on the floor and breathe deeply, and regularly. In, out, in out."

It never occurred to me to argue with him, or to disobey. I sat down on the floor, and I began to breathe, slowly, in and out and out and in and...

In.

Out.

In.

A wrenching. The worst pain I've ever felt. I was choking.

In.

Out.

I was screaming, but I could hear my voice and I wasn't screaming. All I could hear was a low bubbling moan.

In.

Out.

It was like being born. It wasn't comfortable, or pleasant. It was the breathing carried me through it, through all the pain and the darkness and the bubbling in my lungs. I opened my eyes.

I was lying on a metal disk about eight feet across. I was naked, wet and surrounded by a sprawl of cables. They were retracting, moving away from me, like scared worms or nervous brightly coloured snakes.

I was naked. I looked down at my body. No body hair, no wrinkles. I wondered how old I was, in real terms. Eighteen? Twenty? I couldn't tell.

There was a glass screen set into the floor of the metal disk. It flickered and came to life. I was staring at the man in the horn-rimmed spectacles.

"Do you remember?" he asked. "You should be able to access most of your memory for the moment."

"I think so," I told him.

"You'll be in a PL-47," he said. "We've just finished building it. Pretty much had to go back to first principles, come forward. Modify some factories to construct it. We'll have another batch of them finished by tomorrow. Right now we've only got one."

"So if this doesn't work, you've got replacements for me."

"If we survive that long," he said. "Another missile bombardment started about fifteen minutes ago. Took out most of Australia. We project that it's still a prelude to the real bombing."

"What are they dropping? Nuclear weapons?"

"Rocks."

"Rocks?"

"Uh-huh. Rocks. Asteroids. Big ones. We think that tomorrow unless we surrender, they may drop the moon on us."

"You're joking."

"Wish I was." The screen went dull.

The metal disk had been navigating its way through a tangle of cables and a world of sleeping naked people. It had slipped over sharp microchip towers and softly glowing silicone spires.

The PL-47 was waiting for me at the top of a metal mountain. Tiny metal crabs scuttled across it, polishing and checking every last rivet and stud.

I walked inside on tree-trunk legs that still trembled and shook. I sat down in the pilot's chair, and was thrilled to realise that it had been built for me. It fitted. I strapped myself down. My hands began to go through warm-up sequence. Cables crept over my arms. I felt something plugging into the base of my spine, something else moving in and connecting at the top of my neck.

My perception of the ship expanded radically. I had it in 360 degrees, above, below. And at the same time, I was sitting in the cabin, activating the launch codes.

"Good luck," said the horn-rimmed man on a tiny screen to my left.

"Thank you. Can I ask one last question?"

"I don't see why not."

"Why me?"

"Well," he said, "the short answer is that you were designed to do this. We've improved a little on the basic human design in your case. You're bigger. You're much faster. You have faster processing speeds and reaction times."

"I'm not faster. I'm big, but I'm clumsy."

"Not in real life," he said. "That's just in the world."

And I took off.

I never saw the aliens, if there were any aliens, but I saw their ship. It looked like fungus or seaweed: the whole thing was organic, an enormous glimmering thing, orbiting the moon. It looked like something you'd see growing on a rotting log, half-submerged under the sea. It was the size of Tasmania.

Two-hundred mile-long sticky tendrils were dragging asteroids of various sizes behind them. It reminded me a little of the trailing tendrils of a portuguese man o' war, that strange compound sea-creature.

They started throwing rocks at me as I got a couple of hundred thousand miles away.

My fingers were activating the missile bay, aiming at a floating nucleus, while I wondered what I was doing. I wasn't saving the world I knew. That world was imaginary: a sequence of ones and zeroes. I was saving a nightmare...

But if the nightmare died, the dream was dead too.

There was a girl named Susan. I remembered her, from a ghost-life long gone. I wondered if she was still alive (had it been a couple of hours? Or a couple of lifetimes?). I supposed she was dangling from cables somewhere, with no memory of a miserable, paranoid giant.

I was so close I could see the ripples of the thing. The rocks were getting smaller, and more accurate. I dodged and wove and skimmed. Part of me was just admiring the economy of the thing: no expensive explosives to build and buy. Just good old kinetic energy.

If one of those things had hit the ship I would have been dead. Simple as that.

The only way to avoid them was to outrun them. So I kept running.

The nucleus was staring at me. It was an eye of some kind. I was certain of it.

I was a hundred yards away from the nucleus when I let the payload go. Then I ran.

I wasn't quite out of range when the thing imploded. It was like fireworks - beautiful in a ghastly sort of way. And then there was nothing but a faint trace of glitter and dust...

"I did it!" I screamed. "I did it! I fething well did it!"

The screen flickered. Horn-rimmed spectacles were staring at me. There was no real face behind them any more. Just a loose approximation of concern and interest. "You did it," he agreed.

"Now, where do I bring this thing down?" I asked.

There was a hesitation, then, "You don't. We didn't design it to return. It was a redundancy we had no need for. Too costly, in terms of resources."

"So what do I do? I just saved the Earth. And now I suffocate out here?"

He nodded. "That's pretty much it. Yes."

The lights began to dim. One by one, the controls were going out. I lost my 360 degree perception of the ship. It was just me, strapped to a chair in the middle of nowhere, inside a flying teacup.

"How long do I have?"

"We're closing down all your systems, but you've got a couple of hours, at least. We're not going to evacuate the remaining air. That would be inhuman."

"You know, in the world I came from, they would have given me a medal."

"Obviously, we're grateful."

"So you can't come up with any more tangible way to express your gratitude?"

"Not really. You're a disposable part. A unit. We can't mourn you any more than a wasps' nest mourns the death of a single wasp. It's not sensible and it's not viable to bring you back."

"And you don't want this kind of firepower coming back toward the Earth, where it could be used against you?"

"As you say."

And then the screen went dark, with not so much as a goodbye. Do not adjust your set, I thought. Reality is at fault.

You become very aware of your breathing, when you only have a couple of hours of air. In. Hold. Out. Hold. In. Hold. Out. Hold....

I sat there strapped to my seat in the half-dark, and I waited, and I thought. Then I said, "Hello? Is anybody there?"

A beat. The screen flickered with patterns. "Yes?"

"I have a request. Listen. You - you people, machines, whatever you are - you owe me one. Right? I mean I saved all your lives."

"...Continue."

"I've got a couple of hours left. Yes?"

"About 57 minutes."

"Can you plug me back into the... the real world. The other world. The one I came from?"

"Mm? I don't know. I'll see." Dark screen once more.

I sat and breathed, in and out, in and out, while I waited. I felt very peaceful. If it wasn't for having less than an hour to live, I'd have felt just great.

The screen glowed. There was no picture, no pattern, no nothing. Just a gentle glow. And a voice, half in my head, half out of it, said, "You got a deal."

There was a sharp pain at the base of my skull. Then blackness, for several minutes.

Then this.

That was fifteen years ago: 1984. I went back into computers. I own my computer store on the Tottenham Court Road. And now, as we head toward the new millennium, I'm writing this down. This time around, I married Susan. It took me a couple of months to find her. We have a son.

I'm nearly forty. People of my kind don't live much longer than that, on the whole. Our hearts stop. When you read this, I'll be dead. You'll know that I'm dead. You'll have seen a coffin big enough for two men dropped into a hole.

But know this, Susan, my sweet: my true coffin is orbiting the moon. It looks like a flying teacup. They gave me the world back, and you back, for a little while. Last time I told you, or someone like you, the truth, or what I knew of it, you walked out on me. And maybe that wasn't you, and I wasn't me, but I don't dare risk it again. So I'm going to write this down, and you'll be given it with the rest of my papers when I'm gone. Goodbye.

They may be heartless, unfeeling, computerised bastards, leeching off the minds of what's left of humanity. But I can't help feeling grateful to them.

I'll die soon. But the last twenty minutes have been the best years of my life.