As soon as we started, the Ghosts began to gather around us, like vast antibodies. They just hovered there, eerie faceless baubles drifting as if in vacuum breezes. But as I stared up at a dozen distorted reflections of my own skinny face, I felt an unreasonable loathing rise up in me. Maybe you could think of them as a family banding together to protect their young. I didn’t care; a lifetime’s carefully designed hatred isn’t thrown off so easily. I went at my work with a will.

Jeru got through the pod hull first. The air gushed out in a fast-condensing fountain. The baby hides fluttered, their distress obvious. And the Ghosts began to cluster around Jeru, like huge light globes.

Jeru glanced at me. ‘Keep working, tar.’

‘Yes, sir.’

In another couple of minutes I was through. The air pressure was already dropping, and it dwindled to nothing when we cut a big door-sized flap in that roof. Anchoring ourselves with the ropes, we rolled that lid back, opening the roof wide. A few last wisps of vapour came curling around our heads, ice fragments sparkling.

The hide babies convulsed. Immature, they could not survive the sudden vacuum, intended as their ultimate environment. But the way they died made it easy for us. The silvery hides came flapping up out of the hole in the roof, one by one. We just grabbed each one - like grabbing hold of a billowing sheet - and we speared it with a knife, and threaded it on a length of rope. All we had to do was sit there and wait for them to come. There were hundreds of them, and we were kept busy.

I hadn’t expected the adult Ghosts to sit through that, non-aggressive or not; and I was proved right. Soon they were clustering all around me, vast silvery bellies looming. A Ghost is massive and solid, and it packs a lot of inertia; if one hits you in the back you know about it. Soon they were nudging me hard enough to knock me flat against the roof, over and over. Once I was wrenched so hard against my tethering rope it felt as if I had cracked another bone or two in my foot.

And, meanwhile, I was starting to feel a lot worse: dizzy, nauseous, overheated. It was getting harder to get back upright each time after being knocked down. I was growing weaker fast; I imagined the tiny molecules of my body falling apart in this Ghost-polluted space.

For the first time I began to believe we were going to fail.

But then, quite suddenly, the Ghosts backed off. When they were clear of me, I saw they were clustering around Jeru.