Siblings Peter and Annie Garrett (Chris O'Donnell and Robin Tunney) are dedicated mountain climbers. When they, along with their beloved father, are dangerously pushed by a group of amateur climbers, the siblings are faced with a life-altering choice. Their father orders Peter to cut his rope so that Annie and Peter have a chance to survive—an act Annie finds difficult to forgive.

Years pass. Peter works as a nature photographer and Annie for the WNN film team. When she is set to film a commercial with billionaire Elliot Vaughn (Bill Paxton), Annie and Peter meet by chance. The shoot is to take place on K2, the world's second-highest mountain, notoriously difficult to climb.

Despite weather warnings, Annie, Elliot, and leader Tom McLaren (Nicholas Lea) begin the ascent. When the weather worsens, Tom hesitates, but Elliot forces him to continue. Then, disaster strikes! All three plummet into an ice crevasse at high altitude, their lives in immediate danger as altitude sickness sets in.

A rescue expedition of volunteers includes a young woman, French-Canadian Monique Aubertine (Izabella Scorupco), and the loner Montgomery Wick (Scott Glenn)—who lost his own wife on K2. He harbors a terrible suspicion regarding Elliot... Will the small expedition succeed in saving the three?