Quam arrived, flapping his arms, trying to shoo us back. I ducked away, and ran round the other side. The door was open, lying flat in the snow. I crawled in and looked around.

It was a mess. Boxes and bits of kit had been thrown about as though a tornado had hit. Smoke and snow blew through the cabin. I smelled kerosene from somewhere near my feet.

Anderson was the only untouched thing in that chaos. He lay on the stretcher where I’d loaded him up a couple of hours earlier, arms folded across his chest like a dead man.

‘But he made it.’

Franklin stood in the centre of the cabin, staring down at Kennedy. The mummified face looked right back. If there was any expression there, the bandages hid it pretty well.

‘Is there something you want to tell me, Captain?’

No point bluffing. ‘Anderson’s on this ship. He’s hurt, but he’s alive. We picked him up off the ice a few hours ago. He’s the one who told us about the fire at Zodiac.’

Kennedy reached out and scrabbled for the water on the side table. He nearly knocked it over.

‘Let me.’ Franklin tipped the plastic cup to Kennedy’s lips. The water slurped and gurgled in his throat.

‘Have you got someone watching him?’

‘Yeah.’

‘And would he be carrying a gun?’

‘You think—’

Kennedy gripped Franklin’s wrist. Water slopped over the cup’s edge and soaked the bandages.

‘If Anderson’s on-board, you’ll need all the protection you’ve got.’

‘Was he responsible …?’

Kennedy released his grip. ‘Have you spoken to Bob Eastman yet?’

‘He’s still unconscious.’

‘He knows more than me.’

Franklin refilled the cup at the washstand faucet and put it back beside the bed. He picked up the stateroom phone and put in a call to Santiago, on the bridge. Then he sat down.

‘Just tell me it how it happened.’

I opened the Twin Otter’s door, just as I described. Up front, I could see Trond, the pilot, slumped down in his seat. His harness had broken — we found it later several metres from the aircraft. He had a cut to his head, but he was OK. With a little help from Greta, he was able to walk away.

Anderson lay on his stretcher — untouched. At the risk of offending his guardian angel, I’ll take some of the credit for that. I’d worried so much about the flight, I’d wrapped him up like a china doll. I checked his vital signs — all good. The only thing that had come off in the crash was the gas-supply mask. I left it off. If he’d survived that, perhaps he was ready to wake up.

I’m making light of it now, because no one was badly hurt. At the time, we were all shaken, especially the students. Back at the Platform, they gathered in the mess: lots of tears and hugging and cups of tea. I wandered around dispensing comfort and chocolate. When they weren’t looking, I popped another diazepam. Works better than tea, for me.

In between, I shuttled back to check on my patients. As I went past the radio room, I saw Greta sitting in front of the computer talking to someone. I assumed it must be Anderson’s kid — she never called anyone normally. God only knows what she said to him.

Anderson was still asleep in the medical room; Trond was awake, but I’d made him lie down in a bunk to be sure he hadn’t any internal damage.

‘What happened?’ I asked him, shining a light in his pupil.

‘Fuel leak.’ He grimaced. ‘I don’t know how. Everything was checked in Tromsø before we left.’

‘Could you have hit something when you took off? A piece of gravel? A lump of ice?’

‘I doubt it.’ He winced as I changed the dressing on his forehead. ‘But the aircraft is old. Perhaps a seal had broken, or one of the tubes came loose.’

‘Accidents happen,’ I said. If you’re a doctor, you learn to talk in clichés.

‘Yeah,’ he said heavily. Almost as if he didn’t believe me.

There’d been one other person on the plane — though he didn’t much care. When Trond and Anderson were settled, Greta and I drove out to the wreck and fetched in Hagger. There was something grotesque in the way he’d been carted around since he died — sledges, Sno-Cats, crashed planes and still not at rest. Like something out of Faulkner.

There was no telling how much longer he’d have to wait for his eternal peace. The South Pole gang only keep one plane to service Zodiac; the rest are in Antarctica. They’d need a few days, at least, to dig up a replacement, and even then they’d want to take out the wounded first. So I put him on ice.

The cold store’s a spooky place. The ice cover around the base itself isn’t deep enough, so they put it in a glacier just over the hill. As you know, the glacier moves, so every season they have to build a new one. They dig a trench about two metres deep in the ice, cut some steps down to it, then roof it with plywood. As soon as the first snow falls, the plywood’s covered and frozen into the glacier. The room underneath stays chilled steady at ten below, no need for electricity. And if you run out of space, you can just carve out more room from the side walls, like the ancients quarrying out catacombs as they filled up with the dead.

As I say, it’s a spooky place. The snow accumulates, the cave sinks deeper and the stairs get longer. The roof sags under the weight. The only light comes from a few bare bulbs strung from the ceiling; the shadows loom large, especially down the side tunnels. Samples wrapped in plastic rustle as you go past, and it seems to go on for ever.

I loaded Hagger on to the dolly and pushed him to the far end. The body bag I’d put him in was a brittle thing, probably twenty years old, and all that banging about in the crash had torn big holes in it. You could see him inside.

I sliced it off with a box cutter. Underneath, he was still wearing the clothes he’d had on when he died — right down to his glove liners. I hadn’t examined the body properly when Greta and Tom brought him in. Checked the pulse, signed the certificate. Again, I noticed the clothes were stiff and heavy with ice, as if they’d been drenched and then frozen. If he’d been working on sea ice and fallen through, I could have understood it — but he’d been halfway up a glacier.

Down in the dark, something offended me about those clothes. I unzipped the coat, pulled off the hat and worked his hands free of the gloves. It was ridiculous, sentimental, but I thought he deserved a more traditional pose. I lifted his arm and tried to fold it across his chest.

The arm was frozen solid. I bent it as delicately as possible, terrified of snapping it. Too gingerly: it slipped out of my grip. I lifted it again, and as it came into the light I saw the palm of his hand.

It was covered in blood.

I would have screamed, if it hadn’t been for the diazepam. The drug numbed me better than the cold. Instead, I examined the body with narcotic detachment. Hagger had died of a fall; there’d been no puncture wounds. So where could the blood have come from?

It wasn’t blood. Shining my head torch on his hands, I could see the stain was too pink for that. Even in the poor light, it made a shocking splash of colour on his pale skin.

‘Have you started robbing graves now?’

Annabel’s voice was enough to lower the temperature in that room another couple of degrees. I turned slowly. She stood at the bottom of the stairs, framed by the blue light seeping through the ice.

‘The plane shook him about. I’m tidying him up.’

She advanced down the long tunnel. Her breath made icy clouds under the lamps. She stopped at a metal rack full of ice cores and started checking the labels.

‘I had a month’s worth of ice on that flight. Now all it’s good for is cocktails.’

‘And was that the most important thing on the plane, do you think?’