It began on the day when Kendrick Gallmon's heart stopped beating for ever.

The pain crashed down on him suddenly and he sagged, unable to prevent his legs crumpling at the knees. He looked down at the stained interior curve of a toilet bowl and gripped its cool ceramic sides with shaking hands, his ears full of the sound of his own laboured gasping. He vomited noisily, bright agony rushing through his every nerve ending, like wildfire surging through a tinder-dry forest. He watched his knuckles turn white where they gripped the porcelain, and he wondered if he was going to die.

And then, mercifully, the pain began to ease off, leaving him gasping and shivering in the chilly cubicle. He could feel his knees turning damp through his thin cotton jeans. His mouth tasted acid and foul.

Reaching inside his shirt with a couple of fingers, Kendrick touched the bare skin of his chest. It felt cold and smooth, like a marble statue. Next he applied them to his wrist and tried to find a pulse. Finding nothing there, the knowledge sent a chill sweeping through him, so intense that it made his teeth chatter. He moaned in horror, convinced he must have somehow got it wrong.

But he knew the truth. Something had changed inside him, for ever.

Kendrick stumbled to his feet, triggering a series of vivid, dizzying flashes behind his eyes: until it passed, he had to lean with one shoulder against the cubicle's graffiti-stained door. He sucked in air through his nostrils, calming himself steadily.

As suddenly as it had come, the pain washed away, like some Pacific storm leaving a devastated village in its wake. Random, disassociated thoughts tumbled through his mind like flotsam. He glanced down into the toilet and grimaced, before hitting the flusher.

Two long months without a seizure, and now this.

He turned and pushed the cubicle door open. In front of him stood a row of washbasins, under a dirt-streaked mirror mounted on the wall above. The door opened suddenly, admitting loud music mixed with the sound of booze-filled conversation. A man stepped in, letting the door swing shut again, reducing the noise to a low murmur mingled with the muffled thump of bass.

There was something familiar about the other man's face; he looked about late forties, with a black beard turning grey. Kendrick noted the bags under his eyes, which were a pale, watery brown, and how he wore a long woollen coat still damp from the snow.

Those somehow familiar eyes settled on Kendrick, still leaning uncertainly against the cubicle's door frame.

Kendrick experienced a brief bout of dizziness, convinced that there was something important he needed to remember.

"Ken, what the fuck happened to you?"

Peter? Peter McCowan. How could he have forgotten? His thoughts felt muffled, obscured, as if a veil had been hastily drawn over his memories.

Kendrick could see his own reflection in the mirror and realized he looked like shit. He stepped past McCowan and ran water into a washbasin. He splashed some across his cheeks, but it didn't make him feel any better.

"Bad seizure," he replied shakily. He didn't feel up to elaborating.

"How bad?"

"Very bad." Kendrick coughed. "Don't use that name," he added.

"So, what name should I be using?"

"Never my real name, for a start." He leant over and sluiced a jet of water around his tongue, trying to get rid of the lingering taste of acid. He spat the water back into the sink and pulled himself upright, again catching sight of himself in the mirror.

Short-cropped head, narrow face: the same gaunt, fleshless aspect of so many Labrats. Still, he had coped a lot better than most of them, given that most of the Labrats were dead.

In the mirror he could see McCowan behind him, gently shaking his head. "Malky's still out there in the bar, wondering what's happened to you."

"I'll get back to him." Kendrick noticed that his hands still shook slightly. Perhaps that was only nerves and not, as he suspected, indicative of augment-related nerve damage. "It's just something I have to be prepared to deal with," he added over his shoulder.

He glanced up again at McCowan's reflection in the mirror. What is it that feels so wrong here? The longer he paused, the more he was filled with a tremendous sense of unease.

Kendrick closed his eyes against a fresh twinge of nausea. He should just make his excuses, go home, sort something out with Malky another time.

"I'll be frank, you look in bad shape. I don't think Hardenbrooke's treatments have been doing you any good."

Kendrick turned slowly, studying the other man's face. Bright coruscations slid across Kendrick's line of vision, followed by another wash of dislocation. With it a snatch of knowledge: a memory suddenly revealed, as if it had been temporarily locked away in some dark closet of his mind, only now returning with all the subtlety and grace of a drunken punch.

As he almost lost his balance, McCowan stepped forward as if to help. Kendrick backed up against the washbasin and put out a warning hand that stopped him.

"I'll take it you're not okay," said McCowan.

"Something's happening to me." It was starting – he was losing his mind at last. Any notion of finding a cure for what was inside him suddenly seemed far-fetched, laughable. How could he have fooled himself for so long?

"You're going to have to tell me what's wrong," the other man insisted.

Dead man, dead man – the words kept spinning through Kendrick's mind like a mantra.

Peter McCowan, staring up with vacant eyes at the dark ceiling of a lightless storage area, as if that gaze could penetrate the many levels of the Maze to see the sun beyond…

McCowan had moved further away from the door leading back into the bar area. Kendrick lurched past him and gripped the handle, began turning it.

The familiar sound of the bar beyond increased slightly. He paused with the door fractionally open.

"You're not here," he murmured, turning to see if the dead man was still there. McCowan still gazed back at him with calm eyes.

"It was a long time ago."

"I'm sorry."

McCowan cocked his head. "What for?"

"For letting you die."

The other shook his head. "They were never going to let both of us out of there – you know that for a fact. We both knew your family might still be alive out there somewhere. But there was no one who needed me, so I looked like the obvious choice."

This was too much. Over the years he'd imagined what it would be like, to be able to talk to Peter one last time, to find a way to understand what had happened between them. Now it appeared that he had the opportunity, and suddenly he didn't want it. He wasn't ready for it.

It came to Kendrick that he must be caught up in some particularly vivid form of hallucination generated by his augmentations: fantasies that imposed themselves on the real world. How much longer did he have left, then, before he could no longer distinguish the imagined from the real? Was this what it was like for other Labrats when they got close to the end, when their augs consumed first their nervous systems and then their bodies, from the inside out? Did they imagine their pasts literally coming back to haunt them?

If that was the case, then perhaps he would be better off dead.

"I'm here to tell you something. I need to go soon, so are you listening to me?"

Kendrick stared down at the door handle. Sanity lay on the other side of it. "All right, I'm listening."