Meltwater

River and the film crew trade stories about wildlife encounters, while Percy gets some drone footage. Agatha says that base camp has contacted you. There's a storm coming and you need to go – just as the drone is blown out of the sky! Hassan insists that you need to retrieve the drone memory stick and sets off with Percy. You and River decide to go after them, while Agatha and YuJin head back to camp. River has a bad feeling about this.

You catch up with Hassan and Percy. River says that you need to climb onto the nearby moraine – you don't know the terrain in this part of the valley. The snow could cover up crevasses, while the loose gravel of the moraine will give an indication if there is a crevasse ahead. River suggests that you should just let the drone go, but Hassan says that he needs the footage on it. There aren't any do-overs in nature filmmaking.

The clouds are looking a bit ominous. Agatha gets in touch with you from base camp. They got back safely, but the weather report is bad. There's a blizzard coming in and you only have an hour or two before it hits. River wants to turn back, but Hassan refuses and you can't risk splitting up. Onwards it is!

You hear water, and River explains that it's meltwater. The valley that converges with this one has a slightly warmer microclimate, so the glacier there is melting faster. The drone is on the far side of the stream and River points out that you can cross where the moraines converge. Hassan and Percy decide to jump the stream. Percy doesn't make it and begins to slide down the stream towards the hole where the water vanishes into the glacier. You manage to grab him, stopping your slide by using an axe. River and Hassan pull you up, but you're soaked. Hassan still wants to get the drone, so River sends you to fetch it the safe way, while she checks Percy over for injuries.

You return with the drone. The storm is coming and Percy is underdressed after having to strip off his wet clothes. He's padded up with blankets and the foil rescue blanket, but you'll need to get moving quickly. Hassan says that the memory card looks intact. It's important that they rescue this footage so the glacier will be remembered.

Percy isn't doing great and you're down to the last two heat packs. You pass around the chocolate bars from the survival kit, and the water. Agatha contacts you again, saying that they're getting snow already. The storm is coming in faster than expected.

The fastest route back to camp is to cross to the other side of the valley, but this isn't a safe area. Hassan falls somewhere up ahead. He's fallen partway into a crevasse! You pull him up, but he's hurt his knee and when you try to wrap it, you discover that his bag was open and the survival kit is lost. He'll need to lean on you. River will go first, testing the ground ahead. You're running out of time!

You're struggling through snow that's getting steadily deeper, but at least you're out of the crevasse zone! The GPS says it's just a bit further, but the GPS is also getting really cold.

Neither Hassan nor Percy is shivering anymore, which means hypothermia is setting in. Maybe you should dig a shelter? Percy sees lights ahead and River worries that he's hit the hallucination stage, but it's actually the camp! They've turned on every light to help you find it. You hand off Percy and Hassan to Agatha for medical treatment while you go and warm up.

The hot chocolate is warming you up. Agatha tells you that Percy is fine now he's in dry clothes, but Hassan may have broken his leg. He's getting a medical evacuation as soon as the weather lets up enough for a helicopter to reach you. Agatha says that she can handle the rest of the filming and the interviews. She's just glad he's alive. River is glad that you were there. There's no-one better for facing down a mountain!