After his wife dies, Matt Calder (Robert Mitchum) and his young son begin a new life in the breathtaking, rugged Northwest wilderness, where Calder is robbed and beaten by ruthless gambler Harry Weston (Rory Calhoun). When Weston's beautiful fiancée (Marilyn Monroe) then decides to nurse Calder back to health, the insanely jealous Weston risks their lives by taking them all on a ride down a treacherous river in this spectacular looking Western.