The City of the Dead was a sargasso of history, according to him, with strange tides and currents, backwaters and eddies. Everything flowing into everything else.

If they found no intact tombs or abandoned nests, Willie preferred to dowse rather than dig. He would wander over the parched landscape with two lengths of copper wire bent into a pair of L-rods, delicately pinching the short arms between thumbs and forefingers and narrowly watching the quiver and dip of the long arms. Circling a spot when the rods began to twitch, insisting that Lisa start digging if they violently see-sawed.

Willie's dowsing had a surprisingly good hit rate slightly better than chance, according to Lisa's Chi-squared tests but he preferred spelunking, and so did Lisa. Finding their way into spaces untouched for thousands of years, where the psychic traces of the creatures that had built them yet remained. She remembered spiral tombs augered into the earth. She remembered labyrinths of broken stone. She remembered one huge, cool, bottle-shaped chamber lit by a shaft of sunlight from a high crevice. As Willie had climbed down the swaying rope ladder, orange fronds clumped in the splash of sunlight on the floor had suddenly broken up and scurried off in every direction, seeking the safety of shadows. A kind of colonial beetle-thing, it turned out, with symbiotic plants growing on its shells. Lisa remembered another chamber, this one long and low, where eidolons had exploded around them like bats: after they'd sold the tesserae that generated them, she and Willie had lived high on the hog for two months.

She remembered the time the truck's LEAF battery had run out of charge at the western edge of the City of the Dead, a long way from the nearest settlement, with the eroded range of mountains that marked the edge of the Badlands shimmering at the horizon. Willie had pulled his trail bike from the load bed and roared off with the battery strapped behind him. He'd said that he'd be directly back, but a day passed, and another, and there was no sign of him and Lisa couldn't pick up a phone signal. She discovered that she didn't mind being stranded. She had plenty of food, enough water to last a couple of weeks. She slept in the back of the truck's crew cab during the day and watched the starry sky at night. Dissolved into the antique silence of the desert. Looking back, she'd never been happier.

On the fourth day a hot wind out the south blew white sand from the crests of sand dunes. The sky grew milky and the sun faded to a dull smear and the horizon closed in. The truck's door seals couldn't keep out the dust and Lisa had to tie a handkerchief over her nose and mouth. Everything was covered with a fine white bloom. Her eyes itched madly.

Willie drove out of the tail end of the storm towards sunset. He'd been caught up in a business deal, he said, but it hadn't panned out. Lisa didn't bother to ask. It might have been a lead on Elder Culture ruins or a poker game, a girl or a spell in jail. In the morning they mounted the recharged LEAF battery and drove to Joe's Corner and bought water and food and went on.

Those were the days of their lives until they finally hit their jackpot. Until the Bad Trip.

Now here she was again, searching for the origin of the ghost which had driven her away from that life. Grainy and strung out from driving most of the night, watching her rear-view mirror. As soon as she'd hit the eastern edge of the City of the Dead, she'd gone off-road. Navigating by starlight along trackways constructed from ceramic plates laid by an Elder Culture that had left no other trace but these spidery networks.

The trackways had grown rougher as she moved deeper into the City of the Dead, driving deeper and deeper into the past. Her and Willie's past, and the long-gone past of the planet's previous tenants. The past that Willie had uncovered, out in the Badlands. At last, about twenty kilometres north of Joe's Corner, she'd pulled up at the edge of a salt pan, under the shelter of the knitted branches of a cluster of coral trees (they weren't really trees, but a kind of leathery blood-red giant lichen), and dozed in the pickup's cab for a few hours.

As the desert lightened around her, she scanned it for signs of vehicles and checked the sky for drones. She couldn't believe that she had managed to escape, yet here she was, and a strange calm had settled over her. She'd burned her old life and everything was new and strange again.

She ate the last orange segment and pulled out one of her smartphones, checked that she had a signal, and called Bria again. Straight to voicemail. Well, she had tried. She climbed into the pickup truck, started the engine and the phone rang. Bria, according to the display, but Lisa let it ring for almost a minute, thinking hard, before she answered.

'Where are you?' Bria said.

'Out and about. How are you?'

'Worried. Hoping I can talk you out of doing something foolish.'

Lisa felt a prickle of apprehension. She said, 'Let me guess. Nevers has been telling tales out of school.'

'He said that you'd run off,' Bria said. 'And that you could get into serious trouble if you didn't come back right away.'

'Are you in trouble too?'

'Only the trouble I'm already in. Regarding that, he said it would help me if I could persuade you to see sense.'

'I apologise for what went down. The fire. But it wasn't anything to do with the code.'

'It was everything to do with you,' Bria said.

'It was everything to do with Adam Nevers and his Jackaroo pal,' Lisa said, and knew that she was being unreasonable. 'But yeah, I asked you for a favour and it got your business burned down. And I'm sorry for it, I really am.'

'I have insurance,' Bria said. 'And because the police are saying that the fire was caused by a rogue algorithm, the insurers will probably pay up without too much trouble. Meanwhile, fifteen people have lost their jobs. They're good coders, so they'll probably find work elsewhere, but I'll have to start over from scratch. That's okay. I can do it. But I also have to deal with Nevers. He's threatening to revoke my licence. My lawyers say that he doesn't have a case that'll stand up, but he can drag me through the courts and cause me all kinds of trouble. So if you really are sorry for everything you've done, if you really want to help, you should come back and face the music.'

'Nevers let me go,' Lisa said. 'Without a charge. After murdering Pete, by the way. If we're going to talk about losses. Not to mention confiscating and killing my hurklins. So what does he want with me now?'

'All I know is he wants you to come back to Port of Plenty,' Bria said. 'And frankly? I really think you should, before you get into more trouble.'

Lisa remembered that flat unforgiving tone of voice from the time Bria and her other friends had confronted her and, after a fierce three-hour struggle, she'd agreed to go to an AA meeting, her first. And here they were again, Bria telling her what she should do for her own good, but this time Lisa knew that she couldn't take her friend's advice.

She said, trying to explain, trying to be reasonable, 'All it is, I want to find out what happened to Willie. Whether or not it has anything to do with the Bad Trip. Is that so wrong?'

'It's grief,' Bria said. 'You aren't thinking straight.'

'If I can find what caused the Bad Trip, I can fix the ghost in my head.'

'How do you know that what you think you want isn't really what the eidolon wants?'

'I don't. But I'm going anyway.'

'You're throwing everything away.'

'If he doesn't put me in jail, Nevers will probably do his damnedest to make sure I can't work in the Elder Culture biz ever again. So I don't have a whole lot left to lose. I really hope we can sit down and sort things out when this is done. I really do. But if I don't see you again, I just want to say that I'm sorry for everything,' Lisa said, with a rising flush of shame and guilt, and rang off.

She extracted the smartphone's SIM card and broke it and tossed it out the window. It was purely a gesture. She was certain that Nevers had been listening in, that his people had a fix on her location. But fuck it, it was pretty obvious where she would be going next.

26. Colonel X.

One day, Tony found a tightly rolled strip of plastic at the bottom of his morning cup of coffee. When he flattened it out, words began to run from right to left, black on translucent white in a neat handwritten script: We shall meet in the forest at midnight. A servant will show you the way. As the last word followed its predecessors over the left-hand end, the strip faintly fumed and disintegrated into fine ash.

There could be only two possibilities. Either it had been sent by someone who had news or wanted to help him, or it was the work of an enemy who wanted to lure him into an ambush. Not Opeyemi, who would like him to take the blame for everything, but someone else, someone unknown. Tony discovered that he did not much care about the risk. He was excited by the promise of action and the possibility of change. And the form of the message was intriguing. He wondered it had been sneaked into his cup by the farm's supervisor or one of the workers, or perhaps by Lancelot Askia, working as a double agent. He studied the man during that day's constitutional around the perimeter of the farm's snowy fields (he had been forbidden to walk anywhere else after the incident with the kites), but as usual his face was as tightly closed as a fist.

Sleep was impossible, of course. Tony was sitting in the dark in his room, fully dressed, thinking about ways of sneaking past Lancelot Askia and the farm's security, when, at exactly forty-five minutes before midnight, the door opened. One of the farm's hands stood outside, a tripedal servitor like a skinny black bar stool, its flat sensor plate level at waist height. The little machine did not respond to any of Tony's questions as it led him to the mud room. It waited while he pulled on cold-weather gear, then it opened the outer door and led him into the night, across the fields into the pine plantation, heading due north.

The hand skated lightly over the snow, barely leaving any tracks; Tony plodded behind, picking his way by starlight. His face tingled in the cold and his blood tingled too. They crossed the far edge of the pines into the native forest, where spires clad in frosted banners reared into the black sky like rockets of the Space Age, before the Jackaroo had come with their gift of easy travel to other planets. At last, at the edge of a clearing around a frozen pond, the hand halted and a shape detached itself from the shadows between a pair of trees that stood close together.

A tall pale-skinned man drifted forward, dressed in a black jacket and black trousers, dainty black slippers that didn't quite touch the snow. An avatar, a projection.

'I'm glad you came, Mr Okoye,' he said.

'Who exactly are you?'

'Call me Colonel X. These days I work for the Special Services section of the Commons police. I'm sorry that we can't talk face to face, as they used to say. Unfortunately I have to be elsewhere. I'm entertaining an old friend. Someone I haven't seen in an age.'

Colonel X's voice was soft and clear in the stillness of the night; his English strangely accented. His eyes were dark stars in the pale mask of his face. Tony felt as if he'd fallen into an old story about a traveller losing his way in a dark forest and meeting a spirit that offered him his heart's desire in exchange for his soul.

He said, 'You could have called me. It would have avoided a cold walk.'

'Cold for you, not for me. And given the present political climate within your family, any official conversation would have been severely compromised. As would any conversation in your present residence. But we can speak candidly to each other out here, in the presence of God and no one else.'

'Why exactly are you interested in me?'

'Do I need to spell it out?'

'In the spirit of candour.'

'Very well. The archival genetics in the stromatolites. The interest of the Red Brigade in that archive, beginning with your encounter at what you call the Slime Planet. The kidnapping of two wizards and the slaughter of the rest, and the escape of the laminated brain you know as Aunty Jael.'

'You think she escaped?'

'I know that you do. It's a pity your family refused to believe you. It would have made things easier. But here we are anyway.'

Tony realised that Colonel X, whoever he was, must have access to the records of the family council. Perhaps one of his relatives was an agent who could not risk being compromised by openly helping him . . . In any event, it meant that it wouldn't cost him anything to talk frankly. Colonel X must know everything he had to say. He said, 'So what do you want from me?'

'You are in something of a pickle,' Colonel X said. 'I'm here, as the Jackaroo like to say, to help.'

'It was definitely the Red Brigade who claim-jumped the slime planet and was behind the raid.'

'Definitely.'

'And Aunty Jael is not all she seems.'

'She's an acquaintance of mine a sparring partner from days gone by. Someone even older than me, and that's saying something.'

'And the wizard, Eli Tanjung, was not the traitor. She did not contact the Red Brigade. It was Aunty Jael.'

'Indeed.'

'And Aunty Jael poisoned her before she could protest her innocence.'

'Using the neurotoxin favoured by the Reds was a nice touch, wasn't it?'

'What I can't figure out is how Aunty Jael lured Eli to the generator shed.'

'Oh, that's easy,' Colonel X said. 'In addition to the neurotoxin, there were traces of a novel binary drug in Eli Tanjung's blood. Like most wizards, she had been tinkering with her consciousness. And she was also the youngest of the crew, with the lowest status. I believe that your Aunty Jael hooked her on an especially tailored neurological booster, no doubt promising that it would give little Eli an advantage over her colleagues. The usual appeal to vanity I'm sure that a freebooter like you is familiar with the technique. Aunty Jael supplied the drug clandestinely, dose by dose, lured Eli to the generator shed with the promise of more of the good stuff, and killed her before she could protest her innocence. The neurotoxin bolstered your idea that the Red Brigade was involved, so you were happy to believe that the silly young wizard was a traitor who committed suicide to avoid interrogation.'

'At first I was, yes.'

'But then you realised that the Red Brigade must have had inside help. You realised that Aunty Jael could have used her hands to kill the police guards and your servant, and attack your family's troops. And you realised that she had made a deal with the Red Brigade, offering the stromatolites and the Ghajar eidolon in exchange for helping her escape from her bondage with your family.'

'If you know so much, why do you need me?'

'As I said, I'm otherwise occupied at present. But I would very much like to talk to Aunty Jael, and I believe that you will be able to track her down.'

'And what do I get, if I agree to help you?'

'Apart from your freedom, your honour, and your ship?'

'You can do that?'

'Your family have been too busy cleaning up the damage after the raid to get around to putting her on the market. Here.'

It was like a window opening inside his head. The familiar connection streaming in like sunlight through a window. The sense of the shape of the ship and the status of her systems. Tony and the bridle of Abalunam's Pride asking each other if they were all right.

'What have they done to you?' Tony said.

He was on his knees in the snow. He didn't remember falling to his knees.

'They cut off my comms. They would not tell me why,' the bridle said.

'My family were scared of what we found,' Tony said. 'They are still scared. And I am in a little trouble.'

'Of course you are,' the bridle said. 'How bad is it?'

'Nothing that can't be fixed.'

Tony was running a swift and superficial systems check. The ship appeared to be free of any extra layers of security or surveillance. He would need to go deeper to discover if anything had been implanted by his family, and wondered if he would be able to tell if Colonel X had inserted something . . .

And then it all went away again. He was back in the snowy forest, facing the avatar of Colonel X.

'I can give you everything you want,' Colonel X said, 'as long as you agree to help me. And since we both want to find out the same thing, the obligation is hardly onerous.'

'If you really are working for the Commons police, with all its resources, why me?'

'This particular investigation is off the books. Like you, I haven't been able to convince those who call themselves my superiors of the importance of this. So I must work with what comes to hand. If it's any comfort, you are by no means my only irregular.'

'I suppose your superiors refuse to believe that the stromatolites' archival genetics may contain a cure for sleepy sickness.'

'Oh, it was never about that,' Colonel X said airily. 'That was a story got up by your Aunty Jael. Have you been drawing lately? Scribbling?'

'You mean the pattern.'

'I mean the map. The Ghajar found something, long ago. I believe that it has something to do with the so-called mad ships and a certain wormhole route,' Colonel X said. 'As to where that leads, and what's at the end of it, I don't yet know. Something old, something powerful, something that might have destroyed the Ghajar, and may destroy us if it falls into the wrong hands. You should start with the person who pointed you towards the slime planet. The broker, Raqle Thornhilde. She may have collaborated with Aunty Jael.'

'I need some time to consider this,' Tony said.

He wanted to escape his punishment and his shaming, wanted to prove that he was right. And after the brief moments of contact with the bridle, he ached for his ship more than ever. But he also felt a prickling caution: this really did seem like one of the old stories where someone made a pact with a devil, only to find out that the bargain was deeper and more dangerous than it first appeared.

The ghostly avatar of Colonel X said, 'I'm afraid that you'll have to make your decision now. Ten minutes ago someone discovered my tampering with the security system of the farm. And four minutes after that they found that you are not in your room. They are searching the farm for you; it won't be long before they will realise that you escaped, and find the tracks you left in the snow.'

Tony knew that Colonel X could be lying to force his hand, but he also knew that he did not want to return to the farm. He said, 'All I have to do is find Aunty Jael.'

'Yes. What happens after that is up to you.'

'I want full control of my ship.'

'Of course.'

The ship's bridle was back inside his head again, and he was back inside her. She started to apologise for having been cut off; he told her to get ready to boot.

'You bet.'

Tony tore his attention away from her and looked at Colonel X. 'You won't ever touch my ship again.'