'I have just enough of it to be able to fly the mad ship,' Dave said. 'It didn't turn me into a human compass.'

Lisa said, 'Did it show you pictures on the TV?'

Both men looked at her like she was crazy.

She said, 'Mine showed me images of deserts. I think it was trying to communicate.'

'The whole fucking planet is a desert,' Dave said. 'I need a place to set down and I need it now. So you can stop dicking around and give up what you know.'

Lisa said, 'The others in your crew? Were they infected by my eidolon?'

'Like this really is the right time to get into that,' Dave said, with bitter exasperation. 'I had to do what I had to do. Which saved your life, by the way. The others, they were planning to kill you.'

'I think you saved me because we both carry copies of the same eidolon,' Lisa said. 'But it didn't infect your crew, did it? Because they wouldn't have tried to kill me if it had.'

'The eidolon in my head also infected my ship's mind,' Tony said. 'So it's likely, isn't it, that Lisa's eidolon first copied itself into the mind of this ship. A Ghajar eidolon in a Ghajar ship, the two of them becoming something more than the sum of their parts. And then it got inside you, because you are the pilot. Because you interact with your ship's mind.'

Dave Clegg's stare was as narrow as a hawk's. 'So what are you saying?'

'You should trust your ship,' Lisa said.

'Let it choose where to land,' Tony said. 'Some random spot that may turn out to be not so random after all.'

62. Sandstorm.

Tony had once flown a spinner under a thunderstorm on a dare, had realised as soon as the first updraught had flung his little craft into a dense squall of hail that pitting his skill against the storm's raw power was going to be no fun at all. The ride down to the red planet was a lot worse than that.

Dave Clegg wasn't a bad pilot. He knew how to get the most out of his antique interface, used the same manouevre that had helped Tony escape the Red Brigade at the hothouse planet: decelerating hard and letting atmospheric friction kill the rest of his velocity before warping gravity. But as soon as the timeship hit the outer edges of the atmosphere it began to shed parts of its ancient and badly battered fullerene casing, shuddering and shaking as random chunks spalled away, at one point pitching over by at least ten degrees before righting itself. Ghajar ships were tough, but they weren't indestructible, and this one was taking a lot of torque. Its agony squealed and boomed inside the lifesystem like a full orchestra falling down an endless flight of stairs. Lisa Dawes, strapped into the couch next to Tony's, had closed her eyes and her lips were moving in what might be prayer. Dave Clegg hunched at his controls, muttering oaths and imprecations.

At last the awful cacophony and bone-jarring shudders eased off. Dave reported that he had handed over to autopilot so that the ship could choose a landing spot. There was a final wrenching lurch as something big shook free; a couple of minutes later the ship came to rest. Dave conjured a virtual keyboard, entered a string of numbers. A small section of the panelling under the controls dropped down and angled out; he reached inside, unplugged a black tube and removed it, telling Tony, 'You asked about assets. How about a fucking ray gun?'

'You were lucky that the police did not find it.'

'I gave up one just like it, and a bunch of conventional stuff from the armoury. This is my backup. Fully charged, ready to zap any unfriendly BEMs out there. That's bug-eyed monsters, in case you call them something else.'

Lisa said, her voice thin and exhausted, 'We didn't come here to start a fight.'

'Neither did I,' Dave said. 'This is insurance.'

He used a keywand to release the cords that bound Tony and Lisa, and they all climbed down the companionway, now a vertical shaft, Dave chivvying Lisa because she was slow and uncertain, stopping to rest several times before they reached the airlock and the tunnel cut through the fullerene casing. The ship stood on its stern in a warp of local gravity; Dave Clegg deployed a cable winch to lower Tony and Lisa to the ground, a drop of more than fifty metres. Lisa fell to her knees when she reached the ground, breathing so hard her helmet's faceplate fogged on the inside. Tony helped her to her feet, asked her if she was all right; high above, Dave Clegg said, 'She's been fucked up by the wizards. Which is why she should be grateful I rescued her.'

When he followed them down, he let go of the cable a couple of metres too soon and fell flat on his behind. Tony saw a chance to step in and grab the man's ray gun, but hesitated a couple of seconds too long. Dave bounced to his feet in the weak gravity, slapping red dust from the legs of his pressure suit, glaring at Tony and Lisa and telling them they wouldn't find anything by standing around like a couple of dummies.

Tony told himself that if this was going to play out the way he thought it would, the man would be a useful idiot. Let him believe that he was in charge for now.

They had come down somewhere in the planet's high latitudes, in the level light and long shadows of a late afternoon that would last until the dwarf star guttered out in a trillion years or so. A flat landscape of red sand, pavements of dusty red rock, small fleets of scalloped dunes stretching away in every direction. The fat orange sun hung above the horizon in a pinkish cloudless sky.

'There's nothing here,' Dave said, after they had walked out of the shadow of the timeship. He turned a full three-sixty, sunlight flaring on his helmet visor, the ray gun's tube clutched in a gloved paw. 'There's nothing fucking here.'

His voice cracked with frustration. The man had the patience of a toddler.

Tony said, 'We could climb back inside and ask the ship to try again. Another throw of the dice.'

'I've seen maps of this place. Sand everywhere on the sunward side. Ice on the dark side. No,' Dave said. 'We'll keep walking. And you better tell me straight away if you see anything that tickles your eidolons. Because if we don't find something soon I'll have to conclude that you're fucking with me.'

'We are all in this together,' Tony said, trying to calm the man. 'If we do not find anything here, we can look elsewhere. Along the edge of the terminator, perhaps. On tidally locked worlds like this, Elder Culture ruins are usually found along meltwater rivers that flow from the dark-side ice cap.'

'Any rivers dried up a couple of billion years ago,' Dave said, kicking a wedge of sand with the toe of his boot. 'The ice cap is shrunken way the hell back.'

'Then we ask your ship again. Or ask it to call mine down.'

'Don't start that again.'

'I mean only to help,' Tony said, believing that he could use the man's anxiety to get inside his stubborn belligerence. 'My ship's mind has definitely been changed by the eidolon. It may be able to find things yours cannot.'

'I see something,' Lisa said.

She had walked a little way off and was looking up-sun with one hand shading her helmet's faceplate, probably because she didn't know how to polarise it. Tony pulled up a window with an augmented view, but couldn't spot anything other than sand and rock. No alien ruins, no glittering city, no deputation of big-brained ambassadors from a lost race. In the far distance, the horizon looked a little hazier than it had before, perhaps the sky was a little darker . . .

'It's just sand blowing in the wind,' he said.

'It wasn't there a moment ago. It just sort of jumped up. I think it's heading our way.'

Tony used his pressure suit's radar. The signal was faint and fuzzy, but something was definitely moving towards them, moving fast, five or six kilometres a second and rising into the sky as it came on, already turning the sun blood-red.

'Maybe we should get back to the ship,' Dave Clegg said.

'I don't think we have time,' Tony said.

A wind got up around them, blowing dust across the blocky pavement, blowing tendrils of sand that whirled high into the air, thickening into columns and sheets that leaned above them. 'Jesus fuck,' Dave Clegg said, and then the sandstorm hit.

63. City Of Sand.

Lisa was battered to her knees in a jet-engine roar of wind-blown sand, but somehow knew, kneeling there in the stiff pressure suit and the calm bubble of her helmet, that she wasn't in any danger. She remembered a picture in her Grammy's house, a blonde angel with white wings and a white silk robe hovering beside a little boy and girl as they crossed a rickety bridge over a raging torrent, and smiled at the bathos of it. The eidolon was an unknowable alien intelligence, neither angel nor devil, yet she felt stupidly comforted.

It had woken just before the storm had hit. Lisa had found herself staring at the horizon with her ghost at her back, had felt as if clear light had zapped through every one of the optical fibres the wizards had grown in her brain. Wake up! Pay attention! And she was definitely more alert now, was back in her self, back in the world, although she was still bone-tired and soul-bruised, felt as if the wizards had left their grubby fingerprints on every cell of her body. And worse than any damage inflicted by their stupid experiments was the deep aching sense of being irrevocably lost in time and space. Everything she had known, everything that defined her, had been torn away. She had been shanghaied and thrust into the future and there was no way back. No way back to her home. No way back to her life.

Sand smashed into her, hissed over her helmet, accumulated in creases in the material of her suit. Stuttering chains of sparks whirled past and vanished in the dim red rush like the shapes she'd seen flickering in the current of Ghajar narrative code when she'd first opened it, back in Bria's code farm more than a century ago, and she felt herself tugged after those fugitive constellations like a balloon on a breeze, thought that it would be so easy to let go . . .

She was startled back into herself when something Tony Okoye's gloved hand clutched her hand. He leaned in until their helmets were touching; she heard his voice, muffled and distant, telling her to switch off her comms.

'Just look at the speaker icon until it blinks and turns red.'

It took her a moment to work out how to do it. The icon was the usual cup emitting three nested curves of increasing size. Some things hadn't changed. She wondered if people still saved stuff by clicking on an icon that looked like a floppy disc.

'Now we can speak privately,' Tony said.

'This isn't an ordinary storm,' Lisa said.

They were kneeling head to head in the howling blast, holding hands, glove in glove. Tony's face, a handspan from Lisa's, behind the faceplate of his helmet, wore a cool serious expression. There were little scars, precisely spaced, in the skin over the sharp ridges of his cheekbones.

'I think that you and I have woken something,' he said.

'What about Dave?' Lisa said. The man was haunted by a weak copy of her eidolon; she was wondering if he saw what she saw, felt what she felt.

'What about him?' Tony said. 'The eidolon in his head is not like the eidolons in ours. He does not have the connection we share. Perhaps it gave him the idea to escape, to come here, but it is clear that he is out of his depth. He needs us but we do not need him.'

'All hat and no cattle,' Lisa said, and winced as a chain of sparks snapped close to her helmet and blew away.

'We know our eidolons wanted us to come here, but we don't know why,' Tony said. 'But it feels right to me. It feels that we are in the right place. And it is a good feeling.'

'I think the Jackaroo wanted us to come here, too,' Lisa said, and told him about the avatars on Nevers's ship, told him how they had vanished after the expedition had come through the wormhole that orbited the neutron star.

'Unlikely Worlds knows something too,' Tony said.

They told each other how they had met the !Cha.

'He did his best to nudge me towards this place,' Tony said. 'You had the Jackaroo, I had a !Cha.'

Lisa said, 'We were aimed here, no doubt. But we shouldn't blame the Jackaroo or Unlikely Worlds, or even our eidolons. In the end, it was our choice to start down this road. We could have said no to it at the beginning, but we didn't. And now we have to face up to the consequences. It's like Elder Culture tech. People pull it out of ancient artefacts and use it without really understanding it, and when there's some kind of blowback they blame the artefacts, or the Elder Culture that made them. They blame the Jackaroo. They blame everything and everybody but themselves. That kind of thinking is why Nevers wants to control exploration and research. He claims that Elder Culture tech is inherently dangerous, says he wants to protect people from it, but really it's all about taking away the freedom to explore and experiment and create. The freedom to make mistakes. Elder Culture tech can be dangerous, I know that better than most, but every new thing can be dangerous and disruptive if it is misused. There's nothing wrong with exploration and research as long as you take responsibility for what you find, and how you use it. Too many people didn't, in my time. Just as the Red Brigade don't, here and now. As far as I can tell, they aren't interested in Elder Culture tech for what it is. Only in what it can do. How they can use it to gain power over others.'

'As was I,' Tony said. 'As was my family. We fell on hard times. We searched for something that would restore our fortune, and our honour. Ada Morange, as Aunty Jael, encouraged us, and we went along with it. I went along with it. I ended up here because I was chasing a cure for sleepy sickness. I believed that it was lying in some ruin, cached in some eidolon or algorithm, waiting to be found. My family and I, we did not think to find out what sleepy sickness was. What caused it. How it affected people. We just thought that it was bad code, and there had to be good code that would cancel it out.'

'When I won the lottery and went up and out,' Lisa said, 'I thought the same thing. I believed that I would discover something that would make me rich and famous. A lot of people thought like that. They thought that a new world would give them a new life. My husband was one of the few people who actually did make a new life for himself, but most didn't.'

Willie was more than a hundred years dead, but the memory of his last hours was still horribly raw.

She said, 'I helped to create something useful once upon a time, and I gave it away. Because it was got up from found stuff that I didn't own. That no one should own. Because I was young, and still had ideals, and the world seemed full of endless wonders, and there was more than enough time to explore them . . . But I couldn't repeat the trick and I lost sight of why I was doing what I was doing. I became like everyone else, grubbing for trinkets in the dirt. Eyes on the ground, never looking up at the stars. And when we stumbled over something wild and strange, Willie and me, the first thing we did was run away from it. I tried to blot it out with drink and drugs. The usual anaesthetics. The usual attempt to numb yourself against a world that seems too much to handle. The usual refusal. But Willie went on being Willie, more or less. He never gave up the idea that he'd find a way back to that wildness, that strangeness. And he did, but the finding of it killed him. I wanted to know why he died. Because I thought that the world should answer for his death. Because I was scared that it would happen to me. And that's how I ended up here. But the world doesn't owe us any answers. It just is.'

Tony said, 'When Adam Nevers posed as Colonel X, when he offered to help me escape if I would help him, I told myself that I would find something that would redeem myself and restore my family's reputation. But I was really running away. From my duty to my family, from taking responsibility for what happened after I brought back the stromatolites. I blamed my family for driving me away, Adam Nevers for tempting me, my eidolon for leading me on. But it was always my choice. And here I am, at the heart of this great mystery, and I have to ask: do I deserve to be here? What have I done to deserve it?'

'We like to think that we win something from the world because of some innate quality,' Lisa said. 'Because we have been chosen. Because we are anointed. But it's magical thinking. It's observer bias. We see only what we find. We don't see what we miss. We reach a place, a prize, and make up stories to explain why we deserved to get there first, but it's all bullshit. Because if someone else found that prize, what difference would it make?'

'But here we are anyway, making stories,' Tony said.

They were smiling at each other through the faceplates of their helmets, closer in that moment than any lovers. Lisa knew that it might be nothing to do with them and everything to do with their ghosts, but she didn't care.

She said, 'Maybe we're trying to get past the bullshit so we can work out why we're really here, what we hope to find.'

'Whatever it is, Ada Morange and the Red Brigade will try to use it for their own selfish purposes.'

'Yeah, and Nevers will try to stop anyone and everyone from using it.'

'So we must find it before they do.'

'And take control of it.'

'And set it free.'

'Yes,' Lisa said.

'Yes,' Tony said, and lifted his helmet away for a moment before setting it back against hers. 'I think it is getting a little lighter. And wind speed is dropping. I think I see something . . .'

Lisa saw something too. Vague shapes looming through streamers and curtains of blowing sand. The force of the wind against her back was failing, the low disc of the sun was burning through the murk, and then the last of the storm blew past and she saw what it had made.

A city of sand stood all around.

She and Tony pushed to their feet. They were still holding hands, as unselfconscious as children lost in a fairytale wood. Dave Clegg stood a little way off, hands on hips, looking up at a basket-weave tower built of sand. Billions of grains cemented together by some mad architect.

The comms icon inside Lisa's helmet was blinking. She stared at it and Dave's voice was suddenly inside her helmet, saying, 'Are you seeing this?'

'That's Ghajar,' Tony said. 'A Ghajar mooring tower. At least, that's what it looks like . . .'

Dave laughed. 'My ship found the right place after all.'

'Maybe the right place found us,' Lisa said. She was thinking of Willie's last words. A city hidden in a sea of red sand. Thinking that his eidolon and hers had known all along where they were supposed to go. Thinking of the storm front marching towards them across the desert. What had sent it? What kind of intelligence could raise up a city in a few minutes?

Beyond the Ghajar tower, the timeship hung like the gnomon of a gigantic sundial at the centre of a level stretch of sand woven with intricate patterns in shades of red. Avenues radiated away, lined with large and small structures in no discernible pattern. Lisa recognised replicas of Boxbuilder ruins and tombs like the tombs in the City of the Dead, saw in the distance a cluster of huge spires a little like those at Mammoth Lakes, saw untidy piles of spheres, a big cube with a fractal pattern of smaller cubes along its edges . . . Everything the same colour, the colour of blood, everything shining with an inner light, everything tugging at her. Her ghost was leaning in, so close that it seemed to be inside her pressure suit, close as her skin, and she felt an absurd bubbling joy, wanted to fly away down those strange avenues, between those strange buildings . . .

Someone was speaking, asking her was she all right? She had fallen to her knees. Her heart was going like anything. When Tony helped her to her feet she felt the entire world spin around her and everything went dark for a moment. Her body felt brittle and insubstantial, a ghost trapped in the shell of her pressure suit. She had the mad idea that if she stripped it off she could dissolve in the city's lovely light.

Tony asked again if she was all right.

'It's full of light,' she heard herself say.

'The tower?'

'Everything,' Lisa said, but Tony had turned away from her because Dave Clegg had walked up to the base of the tower, was peering at the wall of cemented sand through the curve of his helmet faceplate. He scraped at it, kicked it, then raised the ray gun and started to walk backwards.

'That isn't a good idea,' Tony said sharply.

'I want a sample. Unless you have a crowbar or a wad of C4 in your back pocket, this will have to do.'

'I don't know who made this, or why,' Tony said. 'But I do know that it would not be a good idea to upset them.'

Lisa felt his alarm, or maybe it was her ghost's, and said, 'You could bring the whole thing down.'