On the final leg of their journey, the explorers summit a massive mountain of rock and ice in the Juneau Icefield. As a final farewell gift, Alaska throws a punishing winter storm their way. Expert mountain climber Willi Prittie takes control of the crew from the start. The men try to stay together — and alive — as whiteout conditions worsen, gathering essential survival materials along the way. They proceed up the icy ridges, but one wrong step nearly plunges one of the explorers over the edge.