He stayed curled for another minute, then commanded his limbs to extend. It was time he went subsonic and started manoeuvring. He waited for the shuddering to damp down as he decelerated.

‘Give me tactical.’

His view changed, overlaid with terrain information, targeting graticules, marker flags, laser designators, life support stats, weapons status: it was almost too much to cope with, yet he was used to the flood of data, and welcomed it.

He painted his landing site with a laser, and the halo thrusters kicked in, turning him south and east towards a spot that lay just the other side of a dune from the main dome.

All the time, the ground was rising up to meet him. The thrusters jolted his frame as they guided him in. One minute to go. He hoped Ariadne was right about the air defence.

The domes were still invisible to the naked eye, even though his display told him where they should be. The skimmers on the shoreline were the only evidence anything was there.

Thirty seconds. Twenty . . . ten. The airbags inflated around him like a huge white cocoon. His vision disappeared: only the tactical display remained, a wire-frame representation of the world outside. The numbers counted down to zero. Time was up.

His insides shifted. Accelerometers registered a palpable hit, then he was tumbling over and over. The bags deflated as he rolled, and before he’d come to a halt, he ordered them to jettison.

The bags separated and blew away from him, turning into thick pancakes of ballistic cloth as they leaked their remaining air away. He was left standing, toes splayed on a bed of soft sand.

No one came to greet him. Nor did they try and kill him. He consulted his tactical display and called his remotes to him. As they dropped from the sky, they bobbed close to the ground, then rose again. They gathered behind him, a crowd of glittering spheres in the burning sun.

‘I’m down,’ he said.

‘I can’t see any movement at all,’ Ariadne told him.

‘They probably think you’re going to turn them to ash if they put their heads outside.’ He walked to the top of the dune with difficulty, the sand shifting under the immense weight of the battlesuit. The domes were obvious now, seen side on, the patterns of rock extending upwards in a perfect semicircle. ‘Hard substrate. Tunnels?’

‘There are no emissions, but that doesn’t mean they haven’t gone down. It’s an area notorious for being inhospitable to biological life.’

Benzamir slid down the lee side of the dune. Most of it seemed to slide down with him, and he flexed all his joints below his knees to shake off the sand. The rock shelf that angled down to the sea was far easier, even if it was shimmering with heat haze. The remotes followed him, and fanned out in a wide arc behind him.

The door to the main dome was facing north, and he had to trail around the circumference to get there. He felt himself scanned, acquired as a target by three pop-ups hidden in the encircling dunes. It was an automatic response, and he responded by automatically adding them to his tally of targets.

As he approached the traditional Tribal entrance of three pairs of blast-proof pressure doors, they slid open one after another, revealing a long corridor that led into the heart of the building.

Benzamir hesitated. ‘They want me to go in.’

‘They should come to you. You’re vulnerable under the dome.’

‘They were my friends, Ari. Give me five minutes with them.’ He clustered his remotes and sent them on ahead, in case there was an attempt to separate him from them. Then he followed, using them to scan and spot and give him a picture of what was inside.

The link to Ariadne cut off as soon as he entered the shielded dome.

He walked on, into the open, and stopped to look around. His tactical display lit up, measuring distances, gauging threats. The remotes spun around him, memorizing the architecture and more.

Part of the space was occupied by a triple tier of identical habitats, all grown from the same matrix, their vacant balconies looking out onto a verdant parkland with engineered trees and plants. There was a lawn, and a small lake, and a maze of pathways snaking away towards the outer wall. The glaring overhead sun was filtered to a cool yellow disc that gave only diffuse shadows.

Benzamir recognized the designer in the design.

‘Glad to see Peri’s had time to do some gardening in between slaughtering the locals,’ he said.

A battlesuit moved from among the trees, a shadow of green and brown. It left deep imprints across the grass and finally stopped by the water. It had its own set of remotes, and there was a brief flurry of target acquisition before they settled down again.

One suit pinged the other: neither of them had thought to block the signals, or the information the transponder gave out. Benzamir gave the ghost of a smile when he found out who the rebels had chosen to speak to him.

‘Mahmood. We just can’t seem to keep away from each other, can we?’

‘You knew someone would come for you, Nilssen. I decided that it should be me, because after everything we’d gone through together – all the arguments, the campaigning, the speeches – I thought you’d listen to me. I thought you could be redeemed, and I could persuade the Council to treat you mercifully. Was I wrong?’

‘What do you think? Can you see any way back for us? Or,’ Nilssen said, ‘is the real reason you’re here that you’ve come to join us?’

‘I’ve thought about it. I’ve thought about it often, chasing you across the face of this planet, trying to find you without giving myself away. I’m still tempted.’

‘Then why not? There’s no one to stop you, no one watching what you do. No one to tell you off.’

Benzamir shook his head. ‘It’s too late for that. You have far too much blood on your hands. The monastery of Saint Samuil, the citadel of the Kenyan empire, even your own ship. How could you?’

‘You found her then? All very unfortunate,’ admitted the other man.

‘Unfortunate, Nilssen? You murdered your ship!’

‘She turned against us. We nearly died. We barely made it down in one piece,’ he shouted, and then, as if it would explain everything, he added: ‘She deleted the Great Library.’

It did. Everything finally came together.

‘Is that it?’ said Benzamir. ‘Is that what all this has been about? Dear God. Persephone finally found her conscience: she wiped the library. She’d beaten you, destroyed the one thing you needed. You could have admitted defeat, couldn’t you? Come home and faced justice. But no. You killed her instead.’

Nilssen clenched his giant fists. ‘It wasn’t like that.’

‘Oh no, it was much worse. You made an alliance with the Kenyans: you could trade the tech, but not the knowledge of how it worked. God forbid any of you should remember anything useful!’ Pop-ups rippled across Benzamir’s body, his barely constrained fury leaking through the mental guards. ‘So when you heard of the books, what did you do? You stole them and had all the monks killed. A shelf’s worth of antiques.’

‘We needed them,’ said Nilssen.

‘I’ve heard some crap excuses in my time. Remind me again why you came? I thought the grand plan was to lift everyone up, make them like us. When did you decide to do something different? Not so much the humble servant come to Earth to save it from ignorance and barbarity. More the all-powerful god whose capricious rules have to be obeyed or else. Was that what made Persephone turn on you?’

‘You’re such a sentimental fool. You care too much. Every good leader needs to forget compassion and look at the big picture. You’re not that sort of man, are you? I don’t expect you to understand. When we played together in crèche, you were always the one who did as he was told. Always the follower, little Michael.’

Past taunts burned inside Benzamir. It was all he could do to stop himself from attacking. ‘You have to answer for everything you’ve done. If you don’t surrender willingly to me now, I will take you back in chains – real chains. I know a man who can make them for me.’ He took a step forward, making the ground quiver. ‘It’s your choice, but you haven’t got long to decide.’