Sierra is a backcountry guide in the mountains near the border between British Columbia and Montana. Sierra fled the U.S. years ago because there was a warrant out for his arrest in relation to drug charges and also because he was avoiding the draft. He lives now in a small British Columbia town called Nelson. Sierra takes on a new group who wish to be guided over the mountains and across the border into the U.S. He's aware that the group is probably trafficking drugs; many of his clients are, and it doesn't particularly bother him. These particular clients are all-male and appear to be of many different nationalities, but they are extremely secretive and gruff and insist on protecting their packs at all costs. The group makes slow progress through the snow the first day. George, who appears to be the group's leader, informs Sierra that he cannot sleep in the tents with them, so Sierra builds himself a snow fort to sleep in. The third night of the trip, there is a terrible storm, and Sierra curses himself for not being better prepared for the trip. The group will likely run out of food before they reach the border. George insists that they keep trekking the following day, despite the terrible weather conditions, and Sierra refuses at first until he sees George retrieving a gun from his belongings and promptly changes his mind. When the group crosses a particularly perilous traverse, one of their members, Gord, falls down the steep slope and hits sharp rocks below. His leg is severely broken and he is clearly in awful pain. The group helps Gord into camp that night, and after dinner, Sierra hears everyone conversing in Russian and concludes they are perhaps all part of the Russian mob. The next morning, Gord is dead, foam at the corners of his lips. Sierra realizes the group has murdered him. The next evening, Sierra accidentally lets it slip that he was originally an American, and the group reacts explosively and ties him up. A fight breaks out among members of the camp, and one of them is shot and killed. Sierra sleeps that night tied to George. As Sierra watches the group divvy up the pack contents of the dead men the next morning, he notices they are not transporting drugs, but heavy metal canisters that appear to have electronics in them. That day, they traverse across a vast glacier, heavy fog around them. One of the members falls into a deep, narrow crevasse. There's no way for Sierra to rescue him, and Sierra has lost sight of the rest of the group in the fog. He quickly leaves, headed for the border, with the full knowledge that without him, the remaining men will die of starvation and exposure in the massive glacier. The group, Sierra realizes, is united by their hatred of the United States, and their metal canisters are surely incredibly lethal. He walks onwards without them.