After eighteen years in prison, James Foster (Ralph Morgan) returns to Yellowstone National Park to retrieve stolen payroll and his daughter Ruth Foster (Judith Barrett), arrives to be with him. Also showing up at the lodge are gangsters Marty Ryan (Monroe Owsley) and "Dynamite" (Paul Fix ), detective Hardigan (Alan Hale) and a botanist, Franklin Ross (Rollo Loyd). Foster is murdered and the blame falls on Dick Sherwood (Henry Hunter), a young park ranger in love with Ruth.