December 1943. A German fort sits impregnable atop a mountain. Standing between the Allied forces and their path to Rome is a steep climb up a 200-foot cliff, in the snow, in the middle of the night. As the future of civilisation hangs in the balance, with Axis forces sprawled around the world, a group of highly trained US and Canadian soldiers from humble backgrounds is asked to do the impossible: capture this crucial Nazi stronghold. After completing state-of-the-art training – including skiing, rock climbing and parachuting – they advance upwards, through savage conditions and vicious fighting, into the darkness and towards almost certain defeat.