After killing a man in a bank robbery, outlaw Johnny Lawler is captured, dragged into the small western town of Cactus and jailed. Molly, the childless and lonely wife of Sheriff Marvin Parker, is cleaning the jail house when Lawler arrives and her husband roughly orders her to go home. Molly later returns with food for the prisoner, then noticing his injured hands, brings medicine that she silently applies to his wounds. Early the next morning, the telegraph operator gives Molly an urgent message for the sheriff. Molly wakes her husband who reads the telegram, but when she inquires about its message he tears it up to prevent her seeing it. After picking up the pieces of paper, Molly fixes breakfast and Marvin leaves for the day, instructing her to have Pete relieve Deputy Tom Clements at the jail, but when Molly delivers the prisoner’s breakfast, she tells Tom that the sheriff has requested she replace him. As she hands Johnny his plate, Molly is shocked when he takes her hand to show her that his injuries are healing and thanks her. Johnny tells Molly that she reminds him of his beloved, dead mother and soon they are on a first name basis. Continuing to flatter Molly, Johnny blames her husband for her childlessness, saying that the two of them would easily produce a baby. Molly confides in Johnny that the death of a young prisoner once broke her heart and, showing him the harmonica that the boy gave her, plays him a tune. Attempting to cheer Johnny up, Molly discloses that the telegram revealed that a judge is coming to give him a fair trial, but Johnny is sure he will be hanged because of his undeserved reputation, even though he killed in self-defense. Now crying, Johnny tells Molly that he feels at home having found her and wishes they could have a child together. They kiss and Johnny begs Molly to run away with him, but, saying she must obey the law, she rushes home as Johnny softly curses. That night in bed, when Molly suggests to Marvin that they might still be able to have a baby, he coldly turns his back to her. When Molly asks if the boy in jail will be hanged, Marvin realizes that she read the telegram, slaps her and leaves to sleep somewhere else. At dawn, Molly takes the keys from the jail house desk, lets Johnny out of his cell and they ride away together. Later that morning, after having sex, Johnny quickly breaks Molly’s affectionate embrace and they continue their escape with the sheriff and his posse after them. That night by the campfire, Molly asks Johnny to talk about his mother and he laughs harshly, explaining that he was accidentally conceived by one of several prostitutes, never knowing which one gave birth to him. When Molly responds by saying she understands why he wanted her to be a mother to him, he bluntly replies that he only used her to save himself. This prompts Molly to leave, but Johnny informs her that she will stay with him until he crosses the border into Mexico, adding that she cannot return home after releasing him from jail and that although she is “not much," he can still use her for sex. Molly and Johnny take refuge in a deserted pueblo and when she asks if anything he said to her in Cactus was true, he reiterates that it was “all lies and sweet talk,” finally throwing her harmonica away in exasperation. The next day, an Indian woman comes to the pueblo and goes into labor. Molly helps the woman, who dies after giving birth to a boy. In spite of Johnny’s objections, Molly takes the baby, who she has named “Little John,” with her when they leave. Back in Cactus, Marvin admits to Tom that he hurt Molly and that the prisoner must have taken advantage of her and reveals that to his surprise, he misses her. Later, Johnny and Molly enjoy each other’s company as they bathe and swim, but when she asks if he will take her with him after crossing the border, he does not answer. The following dawn, Johnny is berating Molly over giving their water to the baby when they see a group of Apaches, who soon capture them. Molly and Johnny are tied up and guarded by an old woman who has taken Little John. After Johnny speaks to the woman in her language, she approaches Molly with a knife, cutting off her long hair. The Indian woman then frees them, but when Molly tries to take the baby, Johnny tells her that he has given him away as part of the bargain. Refusing to leave without the child, Molly grapples with the woman as Johnny escapes. After knocking the woman out with a rock, Molly takes the baby and also flees, eventually catching up with Johnny. Soon after, Molly’s horse dies and over her protests, Johnny cuts him up, then cooks the meat and insensitively offers her a bite. Later, Johnny becomes so angry when Molly complains about him letting the squaw cut off her hair and not burying her horse, that he throws her a canteen and leaves her and the baby in the desert while he rides off alone. Molly spends the next day walking through the sand until she finally sees Johnny and he offers her a ride. They arrive at a deserted house where Johnny orders Molly to cross the border into Los Cruses alone. After making him promise to take care of the baby while she is gone, Molly rides into Los Cruces and goes to a house of prostitution asking for Dolly Winward. The beautiful Dolly is suspicious until Molly says she has a message from Johnny Lawler and the two women return to the hideout where Johnny and Dolly passionately kiss, shutting Molly and the baby outside overnight while they make love. Johnny tells Dolly that once he enters Mexico, Molly will be on her own. The next morning, Dolly leaves and Molly goes into town and has the baby baptized, registering his name as John Lawler. The minister recognizes the name and soon a posse surrounds their hideout and in the ensuing gunfight, Johnny and Molly escape through the back. Learning of the baptism, Johnny angrily blames the baby for causing him trouble and prepares to shoot him. When Molly refuses to bring the child to him, Johnny aims his pistol toward them and Molly shoots him first. Standing over him as he dies, Molly says, “I loved you, Johnny” and later rides into Cactus with his body draped over his horse as the townspeople, including her husband, surround her. Calmly announcing that she has the body of Johnny Lawler, who held her captive and forced her to escape with him, Molly then introduces “her” baby as Marvin. After instructing the telegraph clerk to notify Santa Fe that she has Johnny’s body and wants her $2,000 reward, she hands the baby to her astonished husband, who follows on foot as Molly rides home.