Fifteen smokejumpers leapt from a C-47 aircraft on a hot, dry August afternoon in 1949 to engage what was believed to be a routine forest fire burning along the south ridge of the Mann Gulch, a steep, narrow, valley, situated directly east of the Missouri River. Over the next 90 minutes a complex, confusing, and heroic struggle ensued as the fire, fanned by high winds and downdrafts spread in unexpected ways, cutting off firefighters from their planned river escape path and roaring up the gulch with a wall of flame, superheated air and black boiling smoke. In the end, 13 of the firefighters lost their lives. This tragic event dealt a devastating blow to the Smokejumper program and drastically changed the way the Forest Service analyzes hazards and how its fire fighters are trained, equipped, led and deployed.