The Antarctic air was so clear that it was impossible to judge how far away or how high the peaks were. Va was clearly sceptical.

‘If you want, I can show you how the world once looked. It’s very instructive.’ Benzamir hefted the pipe and set off down to the lake shore, scrambling over frost-shattered boulders and skidding on patches of scree.

Va kept pace, and Wahir bounded along with all the recklessness of youth. Said pulled his hood tighter around his face and shivered.

They gathered at the edge of the crust of ice. Benzamir stepped out on it and gave a few exploratory jumps. The surface creaked, but held.

‘Right then, gentlemen. What can you see?’

For Wahir it was all too like being in madrasah again. ‘Can you not just tell us, master?’

‘I suppose I could. That would be novel.’ He spun the pipe in his hands like a quarterstaff. ‘Come with me.’

When they were in the middle of the lake, the creaking noise became so severe that Benzamir ordered them to space themselves out. In a month’s time the ice would have gone, but he couldn’t wait. He swung the pipe high up over his head.

‘What magic does this do, master?’

‘None at all. It’s a bit of pipe.’ He brought it down end on, and the surface crazed and cracked. Again, and he punched a ragged hole through. Water welled up thickly and seeped across the ice. He threw the pipe to Said and unsealed his suit so that he could reach his pocket. He retrieved two light-bees, then sealed himself back up. He tipped the bees in his palm into the hole he’d made. ‘Look down.’

They could see two lights blossom into life, dimly at first, then brighter. They could see the patterns in the clear ice, the bubbles of air caught like flies within its structure.

‘The water is incredibly clear. You should be able to see the bottom of the lake.’

The light-bees burrowed down through the column of water and started to illuminate a shape. The bees moved around it, under it. It was huge, with two inward curving spines and a fat body like a gourd.

‘What,’ asked Va, ‘is that?’

‘I hate to be proved right, especially in this case. It’s Persephone Shipsister.’

Ariadne fretted: ‘My shipsister. What have they done to her?’

‘We’re going to have to get her out of there before we can find out.’

‘She is dead, Benzamir, they’ve killed her.’

‘Ari. We don’t know.’

‘There’s nothing coming from her. I’m trying everything but there’s nothing to get hold of. Everything is offline. This can’t be true.’

‘Try the embryonic remote connection.’

‘It must be atrophied.’

‘I’m sure it will be, but try anyway.’

She was silent while she struggled to secure the ancient protocols. With Persephone as quiet as the grave, it was just possible that she could be crudely controlled by Ariadne as if she was a pre-born ship with no mind of her own.

‘There is . . . something. The bandwidth is almost nonexistent.’

Benzamir turned his heating circuits up another notch and stamped his feet. Wahir and Said had taken shelter in the lee of the craft, and only Va was with him, sucking chill air through his mouth and straight into his lungs. He didn’t seem to be coming to any harm.

‘Can you power her up?’

‘I might, if you stopped talking.’

‘Oh.’

The sun swung round and started its long, slow slide back towards the horizon. Finally the ground trembled.

‘Good work.’

There was nothing else for a while, then suddenly the lake ice cracked, rose, splintered, and fell in cascading sheets of crystal that in turn were bounced up again. A dark shape streaming white water broached the surface, then continued to rise inexorably.

Said and Wahir peered out from behind Ariadne and started to edge back. The circumference of the ship kept on expanding, the ice kept on breaking and sliding, until almost all the lake was on the move. The noise was incredible, a thunderous bass roar with random concussions that made the air vibrate.

The wind caught the water falling from the hull, turned it to ice and blew it in their faces. It forced them to turn away for a moment until the storm was over, and the chunks of ice had finished splashing down into the refilling lake.

Va looked behind him. ‘Bigger than yours, Maghrebi.’

‘And they say size doesn’t matter.’

Persephone Shipsister was three times the length of Ariadne, with two drive pods and a cavernous cargo bay. She spun slowly on her axis, then drifted overhead in search of a landing site. She took a long time to pass by. Ariadne finally brought her down a couple of ship lengths distant, and at an angle. Loose rocks tumbled away, then it was quiet again except for the hiss of the wind.

‘Now,’ said Benzamir, ‘all we have to do is get on board.’

CHAPTER 40

GETTING INSIDE WAS simple once they discovered that Persephone’s main cargo bay doors were open. The ship had been stripped, flooded and abandoned, nothing more than a corpse weighed down with chains and thrown into the deep.

She had been such a magnificent ship. Now she was gone. But Benzamir had to make sure.

They climbed inside the cavernous hold, full of dripping and clammy chill. Their breath condensed in clouds in front of their faces and hung there until swatted away.

Benzamir deployed his light-bees, and sent them up to the ceiling before exploring every dark crevice.

‘Nothing. If it wasn’t nailed down, it’s gone.’ He summoned the bees back. ‘Why would they do this to their own ship? What could they possibly gain?’

Said turned to look back at the daylight. ‘How long has it lain there?’

‘Months. Maybe a year, even. But they landed here, and that doesn’t make sense.’

‘Perhaps they had no choice?’

Benzamir crouched down and drew on the deck with a gloved finger. ‘Nobody say anything, just for a moment.’

They waited for him, listening to the sound of falling water both near and distant.

‘The brain,’ he said. ‘Ariadne, give me the schematics. Stay close,’ he told them. ‘You don’t want to get lost.’

He led them deep into the heart of Persephone, a little bubble of light surrounded by so much darkness.

‘Said, you said they had no choice as to where to land. I think that’s the truth of it. Imagine you had the whole world to choose from: why here? It’s a hostile environment, months of darkness, freezing winds, little in the way of natural resources and no people – the very people you wanted to meet and change. Imagine instead that you were on a ship which you could barely control, which you had to force to the ground by doing the whole finger-of-God, blazing trail through the atmosphere thing. You’d want to land where there were no natives.’ He reached a door, the only one in the whole ship that was closed. He brought the light-bees closer.

The door was deeply scarred and buckled. It had been forced shut and welded so that no one might ever go in again.

Va reached forward and rested his fingertips on the metal. ‘These marks. They had to fight their way in here.’

‘Let’s see what they’ve done.’ Benzamir got out his little laser and began to carefully cut away the welds. When it grew too hot to hold any more, he resorted to using the length of pipe that Said still carried.

When he grew tired, Va took over, hitting the door again and again and again until the whole ship rang with the sound. Benzamir cooled the laser down in a puddle of water, and eventually it worked again.

‘Enough, Brother.’

‘I’m almost through,’ Va said, grunting with effort.

‘I know.’

Benzamir pulsed the laser once through the last remaining weld, and the door sagged. Wahir made to push it, but he was held back. ‘You might damage something inside. The brain is a very delicate thing.’