In August 2008, 25 climbers from several international expeditions converged on high camp of K2, the final stop before the summit of the most dangerous mountain on earth. 48 hours later, 11 had been killed or simply vanished, making it the deadliest day in mountaineering history. In a century of assaults on K2, only about 300 people have ever seen the view from the planet's second highest peak. More than a quarter of those who made it didn't live long enough to share the glory. At the heart of this documentary lies a mystery about one extraordinary Irishman, Ger McDonnell. At the very limit of his physical resources, he faced a heartbreaking dilemma. Through recreations, archive and home movie footage, and interviews with survivors and families, the film creates a forensic, vivid version of events that is emotive, engrossing and, at times, deeply shocking.