Harry Powell (Robert Mitchum) marries and murders widows for their money, believing he is helping God do away with women who arouse men's carnal instincts. Arrested for auto theft, he shares a cell with condemned killer Ben Harper (Peter Graves) and tries to get him to reveal the whereabouts of the $10,000 he stole. Only Ben's nine-year-old son, John and four-year-old daughter, Pearl know the money is in Pearl's doll and they have sworn to their father to keep this secret. After Ben is executed, Preacher goes to Cresap's Landing to court Ben's widow, Willa (Shelley Winters). He overwhelms her with his Scripture quoting, sermons and hymns, and she agrees to marry him. On their wedding night he tells her they will never have sex because it is sinful. When the depressed, confused, guilty woman catches him trying to force Pearl to reveal the whereabouts of the money, she is resigned to her fate but the children manage to escape downriver, with Preacher following close behind.