They both turned. She was holding the ray gun in a two-handed grip, aiming it at Dave Clegg. Its blunt cylinder was surprisingly heavy, trembling in the grip of her stiff gloves. Her heart was beating high and quick, and she was having trouble focusing through the radiance that stained the air around her.

'You wouldn't,' Dave said.

'You might want to step back, Tony,' Lisa said. 'I'm not sure what this thing will do at close range.'

Dave raised his hands to chest height, palms out, saying, 'Maybe things got a little out of control here.'

'You're right-handed, aren't you?' Lisa said. 'Use your left hand to unhitch that bolt gun.'

'You're making a mistake,' Dave said, as he fumbled at his pressure suit's utility belt. 'We have a common enemy.'

'Throw it away as hard as you can.'

He spread his hands and dropped the bolt gun, then turned and started to walk away. Saying, 'I'm going to my ship. If you have any sense you'll come with me.'

'I don't think Lisa was kidding about shooting you,' Tony said.

The man kept walking, saying, 'You think your fucking ghosts can save you against nukes? If you want to live, you should come with me.'

'It's okay,' Lisa said. 'Let him go.'

They watched as the pilot broke into a run, bounding past the Ghajar tower.

Tony drew a '6' in the sand with the toe of his boot, told Lisa how to switch channels.

'All right,' he said. 'He can't hear us now.'

'He wasn't ever listening to us,' Lisa said, and held out the ray gun. 'What exactly is this thing?'

'Elder Culture tech. You didn't have them, in your time?'

'I had a shotgun for varmints,' Lisa said.

'If you like, I can look after it for you.'

'I should throw it away,' Lisa said, but knew that she wouldn't. She might need it if Adam Nevers came back. But first she and Tony had to find what they had been brought here to find. They had to find out what to do with it, or what it wanted to do with them. Even thinking about it was incredibly wearying. All she wanted to do was go home. Return to her home, her land, her life. But everything was lost in time . . .

'What just happened?' Tony was saying. 'The little whirlwind, I mean.'

Shit, she'd had a micro-blackout. 'I think my ghost found a way of using this place. What you said, about your ship. Can it really come for us?'

'I cannot call her down because Nevers's people disabled her comms. But she developed a mind of her own after the eidolon got inside her. She sent the hand that your friend shot, and rescued me another time before that. If she has any sense, she will have escaped from the mad ship after we did, and found some place where she can hang low and wait for an opportunity to find me. That is what I would do, and she knows me pretty well. But if you think I am wrong,' Tony said, pointing, 'I am sure he will still give you a ride.'

Far across the intricately patterned tract of sand, Dave Clegg's tiny figure was rising against the black flank of the timeship, winched towards the tunnel punched into the cladding.

'Run out on all this? No way,' Lisa said. 'Look around you. Can't you see it? The city is alive.'

'See it? See what?'

'The light . . .' She must have had another little blackout, because Tony was gripping her shoulders, shaking her gently, asking her if she was all right. She saw the expression on his face, said, 'What is it? What's wrong?'

He turned her around gently. And she saw.

A pyramid was rising amongst the spires and towers and blocks of the red-sand city. Shouldering its way into the sky like an object growing in the fluid bed of a 3D printer, burning with a lovely golden light that beat with the beating of her heart.

'That can't be real,' Tony said. 'Can that be real?'

Lisa hardly heard him. Something had pulled free deep inside her. Her ghost wrenching away, chasing towards this latest wonder like Pete running after a rabbit across the ordinary scrub and stones of the tableland. There was a moment when she could have let it go. Could have fallen back into herself. Fallen back into the bounds of her plight, and what was left of her little life. But the light was so very lovely, a great ocean of molten gold, a world entire, fierce and beautiful and dense with meaning, and people stood in it, strange people, each possessed by their own particular unearthly grace, and they were calling or singing to her, and although their songs were not in human speech she could understand them.

With a clear plunge of comprehension, like the moment when she had realised how to complete the code for the sandbox rendering, Lisa knew. She knew what the city was. What had been built here. What had been written here by so many, over so much time. And she thought she saw Willie on the far shore of the incandescent ocean, and with a great glad rush she let herself go. Let her ghost carry her along with it, light as air, light as light itself. She tried to call to Tony, tried to tell him what she saw, but she was already dissolving into the city of gold and everything it contained.

66. Pyramid Of The Ancients.

Tony was halfway to the pyramid, trudging down a broad avenue with Lisa in his arms, when the timeship booted. He set his burden down, watched the ship arc up and away, dwindling into a dot, vanishing . . . And reappearing a moment later as a star that briefly rivalled the brightness of the sun, burning up in a cascade of sparks that fell below the horizon.

Tony felt a pluck of sorrow for Dave Clegg. The poor crazy desperate fool. Either Adam Nevers had made good his threat, or one of the Red Brigade's ships had taken out the timeship. It was a bad portent.

He scooped up Lisa's body, set off again. Long shadows painted across wide red streets, across red walls. The column of smoke from the dirty bomb unravelling into the empty sky. No sign of his stupid ship. Tony hoped that she had escaped without harm; that her silence meant that she had not yet found a way to work around the block in her comms, or that she was running silent because she was hiding in deep cover. But if she was coming for him she would have to come soon. His pressure suit was registering life-threatening levels of radiation. In a little over an hour he would require medical treatment; a couple of hours after that the dosage would become critical.

He was utterly alone. He had felt his eidolon leave him when Lisa had collapsed, felt it pull at him as it raced away, felt it vanish. He was certain that Lisa's eidolon had also escaped, and that was why she had died. According to Nevers's wizards, his eidolon was confined to a few tens of thousands of neurons in his temporal lobe, but Lisa's had been deeply embedded, causing anomalous activity in every part of her brain. Just before she had collapsed she had said that the city was alive; Tony wondered if she had followed or had tried to follow the eidolons into the algorithms or energy fields that had raised it up.

Despite his pressure suit's augmentation and the planet's light gravity, Lisa's body was heavy and awkward, the chestplate of her suit rubbing against his, her slack face staring blindly through the fogged faceplate of her helmet. Her suit had tried and failed to restart her heart, reported that there was no activity in her brain. It was cooling her down now. If he could get her to his ship the medical suite might be able to do something, but it was a faint hope.

The pyramid stood massively ahead of him, four-sided, cased in facsimiles of smooth stones, sloping to a summit a hundred and fifty metres high. Plodding towards it, crossing a broad flat space where sand lay in ripples like a beach at low tide, he noticed a minute twinkling in the air above the pyramid's sharp peak, and used the faceplate's zoom facility to capture a close-up. It was a little heart-shaped balloon quilted out of silvery material, a string dangling from the knot at its base. It hung unmoving in the radioactive breeze, just a few metres above the peak of the pyramid's capstone.

He wondered if it was a message from Lisa Dawes. A sign that she was safe. That she was watching over him. Anything seemed possible.

There was a small rectangular opening precisely at the centre of the pyramid's base; it had not been there a moment ago. As he drew closer, Tony saw a glimmer of movement inside, thought for a freezing moment that Ada Morange or Adam Nevers had set some kind of trap. Then, one after the other, three gold-skinned Jackaroo avatars stepped into the sunlight.

They were dressed in the usual black tracksuits, eyes masked by the usual dark glasses. No avatar had ever visited Skadi, and although Tony had seen several in the city of Great Elizabeth, on Rn, when he'd visited with his mother and father that one time, he had never spoken to one. His mother had once told him that the Jackaroo pretended to be interested in people, but they weren't, not really. 'They do not care about who we are,' she had said, 'only about what we can do. Always remember that.'

The three avatars did not greet him, but as he drew nearer they turned and walked into the darkness inside the doorway. He followed them into a passage lit by a pale sourceless light and slanting up to a bell-like chamber at the heart of the pyramid. Plain red walls curved together overhead. A round pool of still dark water was set in the centre of a floor of red sand. Tony imagined billions of sand grains blown on a purposeful wind, each carrying a few molecules of water from the dark side's ice cap to the city. Why not? It was no more incredible than anything else he'd seen today.

Levels of ionising radiation registered by his pressure suit had fallen to the planet's background. Atmospheric pressure and composition exactly matched that inside his suit; the temperature was a brisk fifteen degrees Celsius. He laid Lisa's body on the floor and cracked his helmet, took a cautious sniff, then a deep breath. A faint trace of electricity. Dust. The iron smell of water. A feeling of consecrated calm that reminded him of his family's church, or the archive where documents, mementos, and a small selection of old printed books collected by his great-grandfather and supposedly from Earth were stored.

The avatars stood to one side of the pool, watching as Tony lifted off his helmet and set it at his feet. Somewhere else in the universe the unknown, unknowable intelligences that had shaped them and sent them here were studying him. Intelligences that had gifted humanity with fifteen worlds and watched as people spread across them, digging up fragments of ancient technologies from ruins left by previous tenants, discovering the Ghajar ships and the great wormhole network, moving out across the galaxy. Intelligences that had watched uncountable Elder Cultures flower and fade. Intelligences that professed dispassion and a distancing indifference, yet walked amongst their clients and occasionally intervened in their affairs. To protect people from themselves, or to further some unguessable plan? As an experiment, or out of mischief? No one knew. The Jackaroo claimed that they did not judge, and yet Tony felt judged, standing there in front of the three avatars. They could drive a man mad with a word. They could stop his heart with a gesture. They could read his mind. They knew all.

Their silence compelled him to speak. Remembering something that Lisa had told him, he said, 'Were you the passengers aboard Adam Nevers's ship?'

'Would it matter if we were?' one of the avatars said.

'Would it matter if we came some other way?' another said.

'All that matters is that we are here, and so are you,' the third said.

Their faces, blandly handsome but subtly different, like the faces of three brothers, shared the same calm expression. Their melodious voices were identical.

'If you were on Nevers's ship, you know Lisa Dawes, why she came here,' Tony said.

The avatars did not speak.

He said, 'What happened to her? Why did she die?'

'She is not dead.'

'She has gone on.'

'She is elsewhere.'

'Elsewhere in the city?' Tony really hoped that the avatars were telling the truth, wanted to believe that Lisa was alive, somehow, somewhere. 'It is more than a pile of sand, isn't it?'

'We believe that it was shaped to please you.'

'But not by us. It was never ours.'

'We are visitors, just like you.'

'So this isn't your home world,' Tony said.

The avatars were silent.

He tried another tack. 'If you didn't engineer this world, who did? Who covered it in sand so smart it can build a city in a couple of minutes?'

'You are not the first to have found it.'

'Other clients were here before you.'

'Many have left traces of themselves.'

Tony thought again of the family archive. The hushed windowless room with its rows of steel shelves. Cardboard boxes, books individually wrapped in plastic. The skulls of large animals not found on Skadi hung on one wall, above the table where you could sit and call up documents in its translucent surface. The sense of moveless time. And he remembered something Lisa had said, the things her eidolon had shown her . . .

He suddenly could not stand still. He felt that with one push in the right place everything would fall into a pattern or shape that he could understand. Pacing up and down at the perimeter of the pool, watched by the three avatars, he said, 'The city is a library. A library made of trillions of grains of smart sand. Even if each of them only carries a single bit of information, how much information is that? And the diamond world, the neutron star . . . They are libraries too. One of your client races made this place, downloaded everything they knew into it. And others found it and downloaded everything they knew, too. The Elder Cultures left ruins and artefacts on other worlds, but on this world they left themselves.'

The avatars did not answer, but this time Tony believed that their silence was assent. He thought of the stromatolites and their archival genetics. His adventure had begun in one library and ended in another.

'We know that the Ghajar came here,' he said. 'They left one of their towers on the diamond world, and there is at least one copy of a tower in this city. They came here. They left their records here. And then they had a war and they died out or went away. How many others visited this place? How old is it?'

'You are not the first,' one of the avatars said.

'The Ghajar were not the first.'

'They were far from the first.'

'And I suppose that you have come here to tell me that it is forbidden to us,' Tony said.

He had the ray gun that Lisa had taken from Dave Clegg. He could scythe down the avatars, but what then? The Jackaroo could remake them from air and water. They could make an army, and remake it over and again until the ray gun was discharged and dead. No. Resistance was useless. If they had come here to punish or kill him, let it be quick. A word. A gesture. Merciful oblivion.

'You have found this place early in your cycle,' one said.

'But that is not unusual or unique.'

'We have come to tell you that it is yours now.'

'But you tried to stop us,' Tony said, astonished. 'Isn't that why you were helping Nevers?'

'Every client finds its own path.'

'Whether or not you use this place is up to you.'

'How you use it is up to you.'

'Lisa found a way to use it, didn't she?' Tony said. 'Can I speak to her? Can she speak to me?'

'We aren't here to answer such questions.'

'We aren't search engines or seers.'

'We aren't gods from the machinery.'

'We aren't even gods.'

'We're here to help.'

'As we have.'

'But someone is coming.'

'Perhaps he will give you the help you think you need.'

'But be careful. His help may not be what you want, or all it seems.'

'Who?' Tony said. 'Who is coming?'

But the faces of the avatars were growing dim and indistinct. They were themselves up to the air, fading away without fuss, their dark glasses dropping to the floor, their empty tracksuits collapsing.

A familiar shape was stumping up the passageway; a familiar beguiling baritone said, 'And so you escaped, and found your way here. Ah, but is it a happy ending?'

Unlikely Worlds explained that he had hitched a lift on Abalunam's Pride. 'She was pleased to help me. Eager, even. We spent a few hours hiding in a crevasse in the dark-side ice cap, until she decided that it was safe to emerge, but here we are at last.'

'Where is she? Is she close by?'

'What am I thinking?' the !Cha said. 'You want to talk to her! Please allow me to remove the silly block on her voice.'