In December of 1943, as Nazi forces sprawled around the world and the future of civilization hung in the balance, a group of highly trained U.S. and Canadian soldiers from humble backgrounds was asked to do the impossible: capture a crucial Nazi stronghold perched atop stunningly steep cliffs. The men were a rough-and-ready group, assembled from towns nested in North America's most unforgiving terrain, where many of them had struggled through the Great Depression relying on canny survival skills and the fearlessness of youth. Brought together by the promise to take part in the military's most elite missions, they formed a unique brotherhood tested first by the crucible of state-of-the-art training—including skiing, rock climbing, and parachuting—and then tragically by the vicious fighting they would face.