Lieserl, involuntarily, glanced around the chamber, as if she might see the miniature wormhole threading across space, a shining trail connecting this bland, human environment with the impossibly hostile heart of a neutron star.

“But why?”

“Isn’t it obvious?” Uvarov snapped.

Mark was smiling at her; evidently he had worked it out too.

She felt slow, stupid, unimaginative. “Just tell me,” she said dully.

Mark said, “Lieserl, the link is there so the humans who built this base could reach the interior of the neutron star. I think they downloaded equipment into there: nanomachines, ’bots of some kind — maybe even some analogue of humans.

“They populated the neutron star, Lieserl.”

Uvarov rumbled assent. “More than that,” he rasped. “They engineered the damn thing.”

Closed timelike curves, Spinner-of-Rope.

The nightfighter arced through the muddled, relativity distorted sky; the neutron star system wheeled around Spinner like some gaudy light display. Behind her, the huge wings of the Xeelee nightfighter beat at space, so vigorously Spinner almost imagined she could hear the rustle of immense, impossible feathers.

She felt her small fingers tremble inside gloves that suddenly seemed much too big for her. But Michael Poole’s hands rested over hers, large, warm.

The ship surged forward.

We are going to build closed timelike curves…

Ignoring the protests of her tired back, Louise straightened up and pushed herself away from the Deck surface. She launched into the air, the muscles of her legs aching, and she let air resistance slow her to a halt a few feet above the Deck.

Once this had been a park, near the heart of Deck Two. Now, the park had become the bottom layer of an improvised, three-dimensional hospital, and the long grass was invisible beneath a layer of bodies, bandaging, medical supplies. A rough rectangular array of ropes had been set up, stretching upwards from the Deck surface through thirty feet. Patients were being lodged loosely inside the array; they looked like specks of blood and dirt inside some huge honeycomb of air, Louise thought.

A short distance away a group of bodies — unmoving, wrapped in sheets — had been gathered together in the air and tethered roughly to the frame of what had once been a greenhouse.

Lieserl approached Louise tentatively. She reached out, as if she wanted to hold Louise’s hand. “You should rest,” she said.

Louise shook her head angrily. “No time for that.” She took a deep breath, but her lungs quickly filled up with the hospital’s stench of blood and urine. She coughed, and ran an arm across her forehead, aware that it must be leaving a trail there of blood and sweat. “Damn it. Damn all of this.”

“Come on, Louise. You’re doing your best.”

“No. That isn’t good enough. Not any more. I should have designed for this scenario, for a catastrophic failure of the lifedome. Lieserl, we’re overwhelmed. We’ve converted all the AS treatment bays into casualty treatment centers, and we’re still overrun. Look at this so-called hospital we’ve had to improvise. It’s like something out of the Dark Ages.”

“Louise, there’s nothing you could have done. We just didn’t have the resources to cope with this.”

“But we should have. Lieserl, the doctors and ’bots are operating triage here. Triage, on my starship.”

…And it didn’t help that I diverted most of our supply of medical nanobots to the hull… Instead of working here with the people — crawling through shattered bodies, repairing broken blood vessels, fighting to keep bacterial infection contained within torn abdominal cavities — the nanobots had been press-ganged, roughly — and on her decision — into crawling over the crude patches applied hurriedly to the breached hull, trying inexpertly to knit the torn metal into a seamless whole once more.

She clenched her hands into fists, digging her nails into her palms. “What if the Xeelee are studying us now? What will they think of us? I’ve brought these people across a hundred and fifty million light years — and five million years only to let them die like animals…”

Lieserl faced her squarely, her small, solid fists on her hips; lines clustered around her wide mouth as she glared at Louise. “That’s sentimental garbage,” she snapped. “I’m surprised at you, Louise Ye Armonk. Listen to me: what is at issue here is not how you feel. You are trying to survive — to find a way to permit the race to survive.”

Lieserl’s stern, lined face, with the strong nose and deep eyes, reminded Louise suddenly of an overbearing mother. She snapped back, “What do you know of how I feel? I’m a human, damn it. Not a — a — ”

“An AI?” Lieserl met her gaze evenly.

“Oh, Lethe, Lieserl. I’m sorry.”

“It’s all right, Louise. You’re quite right. I am an artifact. I have many inhuman attributes.” She smiled. “For instance, at this moment I have two foci of consciousness, functioning independently: one here, and one down on the planet. But…” She sighed. “I was once human, Louise. If briefly. So I do understand.”

“I know, Lieserl. I’m sorry.” Louise had never found it easy to express affection. With a struggle, she said: “In fact, you’re one of the most human people I’ve ever met.”

Lieserl looked around at the makeshift hospital, following the soft cries of the wounded. “Louise,” she said slowly, “I have a long perspective. Think of the story of the race. Our timelines emerged from the oceans, and for millions of years circled the Sun with Earth. Then, in a brief, spectacular explosion of causality, the timelines erupted in wild scribbles, across the Universe. Humanity was everywhere.

“But now, our possibilities have reduced.

“Louise, all the potential paths of the race — all the time lines, running from those ancient oceans of the past, through millions of years to an unknown future — all of them have narrowed to a single event in spacetime: here, on this ship, now. And that event is under your control.”

Lieserl’s face loomed before Louise now, filling her vision; Louise looked into her soft, vulnerable eyes, and — for the first time, really she had a sudden, deep insight into Lieserl’s personality. This woman really is ancient — ancient, and wise.

“Louise, you are not a woman — or rather, you are more than a woman. You are a survival mechanism: the best to be found, for this crucial instant, by our genes, and our culture, and our minds. If you didn’t have the strength within you now, to deliver us through this causal gateway to the future, you would not have been chosen. But you do have the strength to continue,” Lieserl said. “To find a way through. Look within yourself, Louise. Tap into that strength…”

There was a deep, almost subsonic groan, all around Louise. It sounded like thunder, she thought.

It was the sound of metal, under immense stress.

She pulled away from Lieserl and twisted in the air. She looked across at the section of hull breached by the arc of string. The patch that had been applied across the string damage gleamed brightly, fresh and polished, at the center of the grass-coated hull surface. A stress failure — another breach of the lifedome — would kill them all. But the patch looked as if it was holding up okay… not that a visual inspection from this distance meant anything.

As if on cue, a projection of Mark’s head materialized before her. “Louise, I’m sorry.”

“What is it?”

“Come with me. We need to talk.”

“No,” she said. Suddenly, she felt enormously weary. “No more talk, Mark. I’ve done enough damage already.”

Behind her, Lieserl said warningly: “Louise…”