Not a western as has often been claimed, River of No Return is a northern, set in Canada during the 19th century Gold Rush. En route to his home, farmer Matt Calder (Robert Mitchum) is beaten and robbed of his horse by gambler Harry Weston (Rory Calhoun). Two people witness this bushwacking: Matts son Mark (Tommy Rettig) and Westons wife Kay (Marilyn Monroe), a dance hall girl. Disgusted by Weston, who has deserted her, Kay elects to remain with Matt as the latter tries to stay alive without provisions in hostile Indian territory. Seeking revenge, Matt builds a raft and braves the rapids, with Mark and Kay in tow, in search of the renegade Weston. When Matt catches up with his prey, it appears for a few minutes that Kay will change her mind and help Weston escape; a quick glance at the billing order of the film will cue the audience as to who will remain alive at fadeout time. Marred only by some unconvincing back-projection scenes, River of No Return is full-blooded entertainment, with both Mitchum and Monroe at their considerable primes. ~ Hal Erickson, All Movie Guide