Shortly before Christmas in 1943, five Army aviators left Alaska's Ladd Field on a routine flight to test their hastily retrofitted B-24 Liberator in harsh winter conditions. The mission ended in a crash that claimed all but one-Leon Crane, a city kid from Philadelphia with no wilderness experience. With little more than a parachute for cover and an old Boy Scout knife in his pocket, Crane found himself alone in subzero temperatures. 81 Days Below Zero recounts, for the first time, the full story of Crane's remarkable twelve-week saga.