Permutation City

She looked back through the doorway. The corridor was still sliding smoothly away, a few centimeters a second. How much further could it go, before the doorway hit a wall, stranding Durham completely?

Swearing, she stepped toward it, and reached through with one hand. The invisible boundary between the environments still let her pass. She crouched at the edge, and reached down to touch the floor; her palm made contact with the carpet as it slipped past.

Shaking with fear, she stood up and crossed the threshold. She stopped to look behind the doorway; the corridor came to a dead end, twelve or fifteen meters away in the direction the doorway was headed. She had four or five minutes, at most.

Durham was still in the garden, still trying to rouse the man. He looked up at her angrily. "What are you doing here?"

She caught her breath. "I missed the launch. And this whole thing's . . . separating. Like the City. You have to get out."

Durham turned back to the stranger. "He looks like a rejuvenated Thomas Riemann, but he could be a descendant. One of hundreds. One of millions, for all we know."

"Millions, where? It looks like he's alone here -- and there's no sign of other environments. You only discovered one communications port, didn't you?"

"We don't know what that means. The only way to be sure he's alone is to wake him and ask him. And I can't wake him."

"What if we just . . . carried him out of here? I know: there's no reason why doing that should move his model to safer territory -- but if our models have been affected by this place, forced to obey human physiology . . . then all the logic behind that has already been undermined."

"What if there are others? I can't abandon them!"

"There's no time! What can you do for them, trapped in here? If this world is destroyed, nothing. If it survives somehow . . . it will still survive without you."

Durham looked sickened, but he nodded reluctantly.

She said, "Get moving. You're crippled -- I'll carry Sleeping Beauty."

She bent down and tried to lift Riemann -- Thomas or otherwise -- onto her shoulders. It looked easy when firefighters did it. Durham, who'd stopped to watch, came back and helped her. Once she was standing, walking wasn't too hard. For the first few meters.

Durham hobbled alongside her. At first, she abused him, trying insincerely to persuade him to go ahead. Then she gave up and surrendered to the absurdity of their plight. Hushed and breathless, she said, "I never thought I'd witness . . . the disintegration of a universe . . . while carrying a naked merchant banker . . ." She hesitated. "Do you think if we close our eyes and say . . . we don't believe in stairs, then maybe . . ."

She went up them almost crouching under the weight, desperate to put down her burden and rest for a while, certain that if she did they'd never make it.

When they reached the corridor, the doorway was still visible, still moving steadily away. Maria said, "Run ahead and . . . keep it open."

"How?"

"I don't know. Go and stand in the middle . . ."

Durham looked dubious, but he limped forward and reached the doorway well ahead of her. He stepped right through, then turned and stood with one foot on either side, reaching out a hand to her, ready to drag her onto the departing train. She had a vision of him, bisected, one half flopping bloodily into each world.

She said, "I hope this . . . bastard was a great . . . philanthropist. He'd better . . . have been a fucking . . . saint."

She looked to the side of the doorway. The corridor's dead end was only centimeters away. Durham must have read the expression on her face; he retreated into the control room. The doorway touched the wall, then vanished. Maria bellowed with frustration, and dropped Riemann onto the carpet.

She ran to the wall and pounded on it, then sank to her knees. She was going to die here, inside a stranger's imploding fantasy. She pressed her face against the cool paintwork. There was another Maria, back in the old world -- and whatever else happened, at least she'd saved Francesco. If this insane dream ended, it ended.

Someone put a hand on her shoulder. She twisted around in shock, pulling a muscle in her neck. It was Durham.

"This way. We have to go around. Hurry."

He picked up Riemann -- he must have repaired his ankle in Elysium, and no doubt strengthened himself as well -- and led Maria a short way back down the corridor, through a vast library, and into a storage room at the end. The doorway was there, a few meters from the far wall. Durham tried to walk through, holding Riemann head first.