River of No Return

River of No Return is a 1954 American Western film directed by Otto Preminger and starring Robert Mitchum and Marilyn Monroe. The screenplay by Frank Fenton is based on a story by Louis Lantz, who borrowed his premise from the 1948 Italian film The Bicycle Thief. It was made in Technicolor and CinemaScope and released by 20th Century Fox.

Kays fiance, gambler Harry Weston Rory Calhoun, tells her they must go to Council City to file the deed on a gold mine he won in a poker game. They head downriver on a homemade log raft, and when they encounter trouble in the rapids near the Calder farm, Matt and Mark rescue them. Harry offers to buy Matts rifle and horse so as to reach Council City by land, and when Matt refuses, Harry knocks Matt unconscious and steals both. Kay chooses to stay behind to take care of Matt and Mark, and the three are stranded in the wilderness.When hostile Indians threaten the farm, the three are forced to escape down the river on Harrys raft. That night they set up camp by the river, and Matt and Kay argue about the wisdom of pursuing Harry. Matt questions why she would choose to marry a man who had endangered a child, and she reminds him Harry never killed a man like he did. Mark overhears their discussion, and Matt is forced to reveal the truth about his past to his son, who is unable to comprehend why his father acted as he did. ........

Source: Wikipedia