The titular river unites a farmer recently released from prison, his young son, and an ambitious saloon singer. In order to survive, each must be purged of anger, and each must learn to understand and care for the others.
Matt Calder, who lives on a remote farm with his young son Mark, helps two unexpected visitors who lose control of their raft on the nearby river. Harry Weston is a gambler by profession and he is racing to the nearest town to register a mining claim he has won in a poker game. His attractive girlfriend Kay, a former saloon hall girl, is with him. When Calder refuses to let Weston have his only rifle and horse, he simply takes them leaving his girlfriend behind. Unable to defend themselves against a likely Indian attack, Calder, his son and Kay Weston begin the treacherous journey down the river on the raft Weston left behind.—garykmcd
The greed of a reckless gambler who has won a mining claim in a poker game forces three people, a farmer named Matt Calder, his son and the gambler's wife, Kay, into an adventure down the river and through the wilderness from which they may never return.—David Rush
Set in the Northwestern United States in 1875, the film focuses on taciturn widower Matt Calder (Robert Mitchum), who recently has been released from prison after serving time for killing a man while defending another one.He arrives in a tent city in search of his ten-year-old son Mark (Tommy Rettig). Mark was to be delivered to Matt by a man named Martin who was paid $100 to bring Mark from Illinois. But Martin arrived early, left Mark in the city and left for the mountains.Mark wandered around the tent city and eventually finds shelter with dance hall singer Kay (Marilyn Monroe). Matt finds Mark and recognizes him from a name label pinned to his coat.Matt promises Mark, a virtual stranger to him, the two will enjoy a life of hunting, fishing and farming on their homestead. Mark says goodbye to Kay and leaves with Matt.The tent city is booming due to the recent excavation of gold in the vicinity.
Kay's 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 their flimsy log raft (Kay had to put up the money to purchase the raft as Harry had none).Meanwhile, at their farm, Matt and Mark enjoy the farm life. The land out west has been recently claimed and is under ever present threat of attack from the displaced Native Americans. Matt teaches Mark how to shoot a gun.They encounter trouble in the rapids near the Calder farm, Matt and Mark rescue them. Harry needs to get to council city, but Matt tells him that the river's route is even worse further on and the rapids are dangerous. The land route is not safe, and Harry would need a horse and a gun to survive the Native Americans who roam the land.Harry offers to buy Matt's rifle and horse so as to reach Council City by land, and Matt refuses. Matt offers to take Harry once the planting in the fields is done in a few days, but Harry is in a rush.Harry knocks Matt unconscious and steals the horse and the gun, along with their food. Kay chooses to stay behind to take care of Matt and Mark, and the three are stranded in the wilderness.
When hostile Native Americans threaten the farm, the three are forced to escape down the river on Harry's raft. That night they set up camp by the river, and Matt and Kay argue about the wisdom of pursuing Harry. Harry wants revenge, but Kay says that Harry was simply acting in his self interest and should not be punished with his life.To save Harry, Kay tries to get rid of the raft, but Matt sees this in time and recovers the raft.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. Matt tries to explain that he person he shot was no good and was trying to kill a friend of Matt's and he had to save him.
As the three continue their journey, Kay comes to appreciate Matt's bravery and the tender way he cares for both her and Mark. The trio get on the raft again and brave the dangerous rapids further downstream. Kay gets drenched in the cold water and Matt saves her life by getting her out of the wet clothes and giving her warmth.But later, as Kay talks about her feelings for Harry, Matt tries to kiss her without her consent.As time passes, they are forced to deal with a series of trials and tribulations, including a mountain lion attack; prospectors Sam Benson (Douglas Spencer) and Dave Colby (Murvyn Vye), who are pursuing Harry for stealing their gold claim; Sam and Dave want Kay to go with them, but Kay says that she wants to stay with Matt. Sam attacks and Matt has to fight him off. Kay is still convinced that Harry is doing the right thing.They also run into another group of Native Americans. This time Matt had the rifle he had taken from Sam and is able to fight off the Native Americans as they go down the river in their raft.
After a difficult ride through the worst of the rapids, the three arrive in Council City and confront Harry. Harry shoots at Matt, forcing Mark to kill Harry with a rifle he is inspecting in the general store, and the boy finally understands why his father shot a man so many years before. Kay also understands that Harry is wrong.
Kay heads to the local saloon, and while she is singing there, Matt arrives to take her back to his farm with Mark.
