‘We should pack our stuff. Kotler could be here any minute.’

  ‘I was thinking the same thing.’

  We broke camp. It was a bright, clear day. Still, almost windless, and eerily quiet. We would hear Kotler’s snowmobile, when he arrived, from a distance. I made another fire and scooped snow into a saucepan to melt over it. The provisions Kotler had left for us included a jar of coffee, so we made black coffee.

  Perhaps the coffee was too strong; it certainly made me want to get on with the day even more than usual. We washed up with snow, put everything away and sat on our packs, waiting for Kotler to show up. Ten o’clock came and went. I banked up the fire, as much to give myself something to do as to ward off the cold. It was much easier to find firewood in the daylight: the fire was soon a big one, its flames flickering head-high.

  Neither of us wanted to say it out loud, but as eleven o’clock slid by I couldn’t help myself. ‘Where the hell is he, do you think?’

  ‘Technically there are still fifty-two minutes of morning left,’ Amelia replied.

  ‘Yes, but I kind of expected him here first thing.’

  Amelia shrugged half-heartedly. ‘Then you expected wrong.’

  North of us – the way from which we’d come – the open snowfield rose gradually in a smooth incline. Pointing that way, I said, ‘I’m going to head up to the ridge and watch for him coming.’

  ‘I can’t see much point in that,’ Amelia said.

  ‘It’s something to do, at least. I’m no fan of waiting.’

  ‘If it makes you feel better, fine. No need for us to lug everything up there though. I’ll wait here with the stuff.’

  I set off. The ridgeline wasn’t far. As I crested it, the expansive plain we’d crossed the day before spread itself out before me, a huge white tablecloth of snow stretched taut across the land. Apart from a few birds flapping lazily overhead, nothing in the scene was moving. I squatted on my heels, squinted at the horizon and waited.

  Amelia was only a few hundred metres away but I felt very alone, marooned in that huge expanse of white. The minutes ticked by. Once I felt sure that midday had passed, I fired up my phone again, relieved to see that, though the battery was low, it had a bar of signal. I called Xander. ‘Is Kotler with you?’ I asked when he picked up.

  ‘No.’

  ‘What time did he leave?’

  ‘What are you talking about? He left with you.’

  ‘Didn’t he return last night?’

  ‘No.’

  I cut across whatever Xander was about to say. ‘About to run out of juice – I’ll see you later.’ I ended the call and switched off my phone, sliding it into my pocket. I stood up and put my hands on my hips. Kotler hadn’t just missed his deadline. For some reason I couldn’t explain, I knew he would not be returning at all.

  34.

  I trudged back down the slope, clear about what we had to do, but fearing that Amelia would take some convincing. But she’d reached the same conclusion as I had.

  ‘Do you reckon you can navigate us back alone?’ she asked when I reached her.

  ‘Yes,’ I said, doing my best to sound more certain than I actually felt. ‘And we should get going now, for two reasons.’

  ‘To maximise daylight,’ Amelia said.

  ‘Yeah, and the other is snowfall. Or lack of it. The snowmobile tracks are still visible – for now. The fact that it’s not been windy should also help; our tracks won’t have been covered by windblown drifts.’

  Kotler had brought much of the equipment – our packs, shovels, bedding and provisions – on a sled he had pulled behind his snowmobile. We had to decide what to take back with us, and what to leave for him to pick up later. We could cram some of the stuff into our packs but – I worried aloud – would we be able to pilot the snowmobiles properly, weighed down like that?

  ‘We don’t have much choice,’ Amelia reasoned. ‘If we get lost and have to spend the night outside, we’ll need all that gear to keep us alive.’

  She was right, but still … Just climbing onto the snowmobile wearing the pack was awkward, never mind negotiating any tricky obstacles with it on.

  ‘Let’s take it slowly,’ I said before we started the snowmobiles. ‘If we stay well within our limits, we’ll be all right.’

  Following the tracks was easy enough to begin with. Kotler had retraced the last part of our route so there were multiple, easily spottable tracks over the same ground. We soon crossed the first expanse and made it into hillier terrain. But among that stubby, snow-enveloped scrub, we came to an apparent fork in the trail. I slowed to a halt, cut the engine, and waited for Amelia to do the same behind me.

  ‘Those are our tracks, heading that way,’ I said, pointing. ‘We crisscrossed each other, coming in from the south-east. But Kotler evidently cut due south here, see? One set of tracks heads that way.’

  ‘Presenting us with a dilemma.’

  ‘Yeah. It’ll be easier to follow our multiple tracks …’

  ‘But we came via a circuitous route. Kotler was showing us how to handle these things’ – I tapped the snowmobile’s handlebars – ‘in different types of terrain. He’ll have headed back the quickest way, I reckon.’

  ‘You’d think,’ said Amelia.

  ‘You sound sceptical.’

  ‘Well, I didn’t say anything at the time, but he drank that vodka before he set off. He could have deviated … unintentionally.’

  ‘I doubt that,’ I said. ‘It looked like he was used to it. I say we go the way he went. If we hit a problem, we can always come back to this point and pick up our trail.’

  Amelia adjusted her helmet, shrugged and nodded, and we carried on our way.

  Kotler’s return trip cut through sparse woodland. He’d woven through the trees, heading gently downhill, before picking up a path that wound its way between low-lying hills. I’d been following this open stretch a good few minutes before I realised it was a frozen stream. The going was easy, level, a series of gentle curves that soon joined another tributary and broadened into a bigger river. Kotler’s tracks hugged the left-hand bank for a mile or so. Then the river swung lazily to the south-west and opened out further into what had to be a lake. The tracks made by Kotler’s snowmobile set out straight across it, then gradually veered to the east.

  I was tempted to open up the throttle as we followed his route across this expanse, but something stopped me. It was the colour of the snow ahead: the bright white immediately in front of us softened to a weird grey. In fact, fifty or so metres away, closer to the far shore than the one behind me, it looked like there was an abrupt strip of … black.

  I brought the snowmobile to a halt and motioned for Amelia to follow suit.

  ‘Something’s not right,’ I said, setting my pack down on the seat of the snowmobile. ‘Look.’ I pointed. ‘What’s that?’

  Amelia narrowed her eyes. ‘Oh my God.’

  I set the GoPro to record and took a step forward.

  Amelia put her hand on my arm. ‘Wait. If we’re going to do that, let’s do it like this,’ she said, lowering herself to all fours. ‘To spread our weight.’

  I dropped to my hands and knees beside her, and we crawled across the grey ice. We covered the ground slowly, following the snowmobile’s tracks. I was hoping against hope that they would change course, but they headed straight towards the black hole ahead. Amelia spelled things out as we went. ‘He was travelling in the dark. The snowmobile’s headlights tinge everything yellow. And he’d been drinking. He could well have cut straight across this without seeing the colour change.’

  ‘But why would one bit of the lake ice be thinner than the rest?’ I asked.

  ‘It could be a thermal current of some sort, a spring,’ said Amelia.

  ‘Surely he’d have known about it?’

  ‘You’d have thought, but although it’s not exactly warm, it’s usually colder than this here. Maybe the ice is unusually thin. Hold on. Shh.’

  We halted. The silence felt huge, but actually it was underscored by a faint hum, a bit like the kind you hear if you stand near an electricity pylon. The ice seemed to be singing beneath our weight. By now we were only eight or so metres from the hole. Dropping to my belly, I leopard-crawled another three or four metres. The snowmobile’s tracks ploughed straight into the shimmering black water. Another metre on, I levered myself up on my hands, and saw a flash of orange deep beneath the surface.

  ‘I can see it,’ I said.

  ‘What?’

  ‘The snowmobile,’ I said. ‘But there’s no sign of Kotler. He could have clawed himself free.’

  ‘He wouldn’t have tried that,’ said Amelia.

  I swivelled to face her. ‘Why not?’

  ‘Clawing at the edge of the ice just risks breaking more of it off. You have to kick your legs up behind you and keep kicking, pulling with your arms if you can, sort of swimming yourself up onto the ice, staying as flat as possible the whole time. Then once you’re onto firm ice, you roll away from the hole. Can you see any drag marks?’

  I looked left and right, but couldn’t see any sign that Kotler had pulled himself to safety.

  ‘Look for pick holes,’ she added. ‘Snowmobilers sometimes carry little screwdriver-like picks – you can even get them to wear around your neck. They use them to jab into the ice and get a hold on it. He could have had some on him. If you know you’re going to be snowmobiling over thin ice, they’re a worthwhile precaution …’

  I know Amelia well; she was trying to make herself feel better with this knowledge, avoiding thinking about what actually seemed to have happened to Kotler. I searched for any pick-marks in the ice but found none, and told her so.

  ‘Come away from the edge then.’ There was resignation in her voice.

  Gingerly, with the ice creaking and the full horror of Kotler’s accident sinking in, I slid away from the hole.

  35.

  ‘We need to mark this location,’ I said, reaching for my phone. It had just three per cent of battery life left when I turned it on, which meant it could die at any time. Working quickly, I opened the What3Words app and read the three words the screen showed me, angling the screen Amelia’s way so she could double-check. ‘Imagined.Fluctuate.Problematic.’

  ‘Imagined.Fluctuate.Problematic,’ she repeated.

  ‘That’s the GPS-located square metre of the planet we’re currently standing on.’

  ‘It’s actually a three-square-metre location, and technically we’re on our hands and knees, but yes, I know.’

  ‘Whatever. If we remember those three words and give them to the emergency services or whoever, they’ll be able to come here and … investigate.’

  ‘Imagined.Fluctuate.Problematic,’ Amelia said again. ‘Got it.’

  This mini-achievement wasn’t much to cheer about, but it gave me an idea I couldn’t believe I hadn’t thought of before. Trying not to sound too hopeful, I asked Amelia how much battery life her own phone had.

  ‘Not much. I took a fair bit of video with it yesterday.’

  ‘Not much, but some?’

  She looked. ‘Sixteen per cent.’

  I steeled myself to ask the question. ‘And have you downloaded the What3Words app yourself?’

  ‘After you mentioned it I did, yes, obviously.’

  I puffed out my cheeks with relief. ‘It has a navigation function. You don’t even need data to use it. If Xander sends us his location, we can use the compass feature on the app to get back to him.’

  I’d texted Xander and Amelia as I explained this, saying simply Pls txt me + A yr W3W locn asap. My phone took an age to send the message, but Amelia’s pinged in response. Instantly the screen in my hand went black. No matter: if Amelia had received it, Xander would too, surely?

  We knelt there, staring at her phone screen. It felt like nothing happened for aeons; in fact, Xander replied in just two minutes: ‘Retrieving.Surer.Deafened.’

  Amelia’s phone was already on low power mode. I watched as she shut down all the apps apart from What3Words. With ‘Retrieving.Surer.Deafened.’ in the search bar, she hit the compass feature. Instantaneously it locked onto a destination a little over fourteen kilometres away, with the big red compass arrow pointing south-south-east across the frozen lake.

  ‘Why did Kotler go this way?’ I wondered aloud. ‘If he’d carried on straight, he wouldn’t have run across the thin ice.’

  ‘Beats me,’ Amelia whispered. ‘Should we trust the phone and follow the compass, or retrace our steps, pick up our old tracks, and follow them?’

  ‘Turn off the phone for now,’ I said. ‘But I reckon we should trust it. Fourteen kilometres won’t take long on a snowmobile, especially over easy terrain. Kotler was taking the quick route home. This close to his own facility, he must have known the territory. But he turned off the direct route home and ran into this weak patch – it makes no sense at all.’

  ‘Unless …’ Amelia began.

  I finished her thought for her. ‘You think he could have fallen asleep at the wheel?’

  ‘It’s a stretch, but what other explanation is there? This open patch is pretty much the easiest to ride across, and a slug of weapons-grade vodka wouldn’t exactly have helped him stay awake.’

  We’d retreated – on all fours at first, then walking carefully – to our own snowmobiles as we talked. I slung my pack over my shoulder and climbed back into the saddle. ‘I vote we head south-south-east at fourteen kilometres an hour – or as near as dammit – for sixty minutes, then we can use the compass on the app to zero in on Kotler’s place.’

  ‘Seconded,’ said Amelia. ‘You’ve got a sense of direction like a homing pigeon, so you lead and I’ll follow.’

  ‘And let’s keep an eye out for odd-looking patches of snow as we cross the lake. I want to get off it in one piece.’

  ‘Also seconded,’ said Amelia.

  Standing tall in the saddle to scan the snow as far ahead as possible, I led the way across the frozen lake. Fourteen kilometres an hour felt so slow. I couldn’t help thinking about what had apparently happened to Kotler. Could he really have fallen asleep driving a snowmobile? Despite my helmet, the wind on my neck was biting, even at that slow speed, and the engine noise was still a distraction. There was no way I could have drifted off while driving, but then again, the experience was new for me. Kotler drove snowmobiles all the time.

  If we were right and he’d dozed off, veered towards the thin ice and crashed through the surface, the first he’d know about it would be the vicious slap of cold as he plunged into the icy water. It was dark. He’d have been disorientated, and he could have been dragged down by the snowmobile.

  If he’d been pulled deep enough, he might even have bobbed under the ice, away from the hole. My experience in the avalanche had been hideous enough. If the snow had been freezing water … it didn’t bear thinking about.

  I tried to be methodical, scanning the snow ahead, looking for any discoloration at all, relieved to find none. Within ten minutes we’d made it safely to the reassuring undulations of solid ground. There were plenty of tracks through the bushes on this side of the lake. I picked up a route that headed in the right direction and tried to maintain a constant speed along it.

  My eyes were still trained on the horizon, but after a time a quick movement made me glance to my left. An Arctic hare had stood up on its hind legs to survey us. It looked as if it was being pulled taut by an invisible string. As we passed, the string snapped and the hare morphed into a streak of white, disappearing across the snow.

  The clock on the snowmobile’s instrument cluster told me we’d been going for forty-five minutes. Shortly afterwards we came to a dense clutch of pine trees. The tracks I was following skirted them, so I did the same; though this meant leaving the south-south-east heading, the trees grew so close together that we had no choice. Just before the hour was up, I brought us to a halt and Amelia re-checked What3Words. While she was explaining that we were now within two kilometres of Kotler’s place, but that it appeared to be back around the woods we’d skirted, a message landed from Xander.

  Get back quick. Caleb in bad way. Shockwave situation serious, it said.

  Since she still had more than ten per cent of battery life, I decided to keep the compass screen open and follow it, as fast as we could. In no time we were tracking round the far side of the woods. I sensed we were nearly there and the app agreed with me – or it could have been the other way around. We crested an incline. In front of us Kotler’s facility was spread out, only a couple of hundred metres away.

  I should have been elated to see it. But Kotler’s apparent accident and Xander’s text had filled me with dread and fear. We were arriving back all right, but ‘back’ was still the middle of nowhere, a long way from help for Caleb. And what exactly did ‘Shockwave situation serious’ mean?

  36.

  Xander must have heard the snowmobiles approaching. He was in the yard waiting for us. His hair was sticking out at odd angles: it looked like he’d literally been pulling it out with worry.

  ‘Caleb’s sick,’ he said by way of a greeting. ‘He’s not right at all.’

  ‘What sort of not right?’ Amelia asked.

  ‘He has a fever, and he spent half the night thrashing around in bed talking nonsense.’

  ‘He’s delirious, you mean?’ said Amelia, dumping her bag on the floor.

  ‘Something like that. At one point he tried to get dressed, saying he was going to walk home. When I stopped him, he took a swing at me then collapsed. And now he’s out cold. I can’t wake him up.’

  We’d moved through into the bunk room, where Caleb was in bed. He was curled on his side, the hood of his sleeping bag pulled tight over his head. I knelt next to him. ‘Caleb, it’s me, Jack.’

  He didn’t say anything, but a shudder went through him. I put my hand on his shoulder and could feel him shivering.

  ‘When did he last drink?’ Amelia asked.