After serving a prison sentence, farmer Matt Calder (Robert Mitchum) returns to his 19th-century Pacific Northwest gold rush town and retrieves his adolescent son, Mark (Tommy Rettig). Meanwhile, goodhearted barroom singer Kay (Marilyn Monroe) is heading downriver with her boyfriend, Harry (Rory Calhoun), to explore a potential gold claim. When their raft sinks, Harry robs Matt of his gun and horse to continue without Kay on land. Sailing downriver toward the claim, the trio plan their revenge.