"It would only be a quarter Culture, Horza, if you want. I'm sorry to leave it to you. But if you don't want to know, OK; I'll think again and make my own decision. It's still part of me, so maybe I don't have any right to ask you. I don't really want to…" She sighed mightily. "Oh God, I don't know, Horza, I really don't."

"Yalson," he said, having thought about what he was going to say, "I don't give a damn your mother was from the Culture. I don't give a damn why what has happened has happened. If you want to go through with it, that's fine by me. I don't give a damn about any cross-breeding either." He pushed her away slightly and looked into the darkness that was her face. "I'm flattered, Yalson, and I'm grateful, too. It's a good idea; like you would say: what the hell?"

He laughed then, and she laughed with him, and they hugged each other tightly. He felt tears in his eyes, though he wanted to laugh at the incongruity of it ail. Yalson's face was on the hard surface of his suit shoulder, near a laser burn. Her body shook gently inside her own suit.

Behind them, in the station, the dying man stirred slightly and moaned in the cold and darkness, without an echo.

He held her for a little while. Then she pushed away, to look into his eyes again. "Don't tell the others."

"Of course not, if that's what you want."

"Please," she said. In the dimmed glow of their suit lights, the down on her face and the hair on her head seemed to shine, like a hazy atmosphere round a planet seen from space. He hugged her again, unsure what to say. Surprise, partly, no doubt… but in addition there was the fact that this revelation made whatever existed between them that much more important, and so he was more anxious than ever not to say the wrong thing, not to make a mistake. He could not let it mean too much, not yet. She had paid him perhaps the greatest compliment he had ever had, but the very value of it frightened him, distracted him. He felt that whatever continuity of his name or clan the woman was offering him, he could not yet build his hopes upon it; the glimmer of that potential succession seemed too weak, and somehow also too temptingly defenceless, to face the continuous frozen midnight of the tunnels.

"Thanks, Yalson. Let's get this over with, down here, then we'll have a better idea what we want to do. But even if you change your mind later, thank you."

It was all he could say.

They returned to the station's dark cavern just as the drone pulled a light sheet over Neisin's still form. "Oh, there you are," it said. "I didn't see any point in contacting you." Its voice was hushed. "There wasn't anything you could have done."

"Satisfied?" Aviger asked Horza, after they had put Neisin's body with Dorolow's. They stood near the access gantry, where Yalson had resumed guard duty on the unconscious Idiran.

"I'm sorry about Neisin, and Dorolow," Horza told the old man. "I liked them, too; I can understand you being upset. You don't have to stay here now; if you want, go back to the surface. It's safe now. We've accounted for them all."

"You've accounted for most of us, too, haven't you?" Aviger said bitterly. "You're no better than Kraiklyn."

"Shut up, Aviger," Yalson said, from the gantry. "You're still alive."

"And you haven't done too badly, either, have you, young lady?" Aviger said to her. "You and your friend here."

Yalson was quiet for a moment, then said, "You're braver than I thought, Aviger. Just remember it doesn't bother me a bit you're older and smaller than me. You want me to kick your balls in…" she nodded and pursed her lips, still staring at the limp body of the Idiran officer lying in front of her, "… I'll do it for you, old boy."

Balveda came up to Aviger and slipped her arm through his, starting to lead him away as she walked by, "Aviger," she said, "let me tell you about the time-" But Aviger shrugged her away and went off by himself, to sit with his back to the station wall, opposite the reactor car.

Horza looked down the platform to where the old man sat. "He'd better watch his radiation meter," he said to Yalson. "It's pretty hot down there near the reactor car."

Yalson gnawed at another ration bar. "Let the old bastard fry," she said.

Xoxarle woke up. Yalson watched him regain consciousness, then waved the gun at him. "Tell the big creep to head on down the ramp, will you Horza?" she said.

Xoxarle looked down at Horza and struggled awkwardly to his feet. "Don't bother," he said in Marain, "I can bark as well as you in this miserable excuse for a language." He turned to Yalson. "After you, my man."

"I am a female," Yalson growled, and waved the gun down the ramp, "now get your trefoil ass down there."

Horza's suit AG was finished. Unaha-Closp couldn't have taken Xoxarle's weight anyway, so they would have to walk. Aviger could float; so could Wubslin and Yalson, but Balveda and Horza would have to take turns riding on the pallet; and Xoxarle would need to foot-slog the whole twenty-seven kilometres to station seven.

They left the two human bodies near the doors to the transit tubes, where they could collect them later. Horza threw the useless lump of the Mind's remote drone to the station floor, then blasted it with his laser.

"Did that make you feel better?" Aviger said. Horza looked at the old man, floating in his suit, ready to head up the tunnel with the rest of them.

"Tell you what, Aviger. If you want to do something useful, why don't you float up to that access ramp and put a few shots through the head of Xoxarle's comrade up there, just to make sure he's properly dead?"

"Yes, Captain," Aviger said, and gave a mock salute. He moved through the air to the ramp where the Idiran's body lay.

"OK," Horza said to the rest; "let's go."

They entered the foot tunnel as Aviger landed on the middle level of the access ramp.

Aviger looked down at the Idiran. The armoured suit was covered with burn marks and holes. The creature had one arm and one leg missing; there was blood, dried black, all over the place. The Idiran's head was charred on one side, and where he had kicked it earlier Aviger could see the cracked keratin just below the left eye socket. The eye, dead, jammed open, stared at him; it looked loose in its bone hemisphere, and some sort of pus had oozed out of it. Aviger pointed his gun at the head, setting the weapon to single shot. The first pulse blew the injured eye off; the second punched a hole in the creature's face under what might have been its nose. A jet of green liquid splashed out of the hole and landed on Aviger's suit chest. He splashed some water from his flask over the mess and let it dribble off.

"Filth," he muttered to himself, shouldering his gun, "all of it… filth."

"Look!"

They were less than fifty metres into the tunnel. Aviger had just entered it and started floating towards them, when Wubslin shouted. They stopped, looking into the screen of the mass sensor.

Almost at the centre of the close-packed green lines there was a grey smudge; the reactor trace they were used to seeing, the sensor being fooled by the nuclear pile in the train behind them.

Right at the very edge of the screen, straight ahead and over twenty-six kilometres away, there was another echo. It was no grey patch, no false trace. It was a harsh, bright pinpoint of light, like a star on the screen.