Gary Cooper plays a frontier doctor with a checkered past who works in a rowdy Montana mining camp. Cooper falls in love with Maria Schell, a young Swiss girl whom he has treated for shock after she was the victim of a holdup. He finances Schell's grubstake, which makes her rich. When Schell's unscrupulous partner Karl Malden tries to have his way with the girl, Cooper kills Malden. Sentenced to an immediate hanging, Cooper is saved when Schell offers to give the town her valuable mine. A surprise hit in 1959, The Hanging Tree was based on an award-winning novel by Dorothy M. Johnson. The film not only yielded a hit theme song by Mack David and Jerry Livingston, but also served as the film debut of George C. Scott, who plays Cooper's doctor predecessor.
~ Hal Erickson, All Movie Guide