Grimpeurs: In 1961 the southern face of the Central Pillar of Mont Blanc was still unclimbed. Two roped parties of climbers decided to come together to attempt to open a new route. Four days of violent storms caught the climbers just 80 metres from the summit. Of the seven climbers, only three returned home. One of the most intense and dramatic events in the history of climbing relives on the big screen, thanks to accounts and images of the feat.