In 1936 Ernest Tinnion leaves England for Switzerland to climb, with his childhood friend Hansi Kirchner, the awesome north face of the Versucherin. As they prepare the ascent, unforeseen pressures mount: from Tinnion's lover, who has left her husband to join him; from a too curious, menacing German photographer; and from a rival Italian team. In a breathtaking climax, Tinnion is forced to weigh survival against loyalty, neutrality against love and friendship, and to recognise ominous parallels with the looming global conflict.