In the cattle town of Lost Valley, Buck Courtrey, saloon owner and political boss, covets Tharon, daughter of Jim Last, a small rancher; and when rebuffed, he has Last killed. Tharon swears revenge with her father's own guns and organizes a vigilante band to check Courtrey's activities. Learning that she loves Billy, a cowpuncher, Courtrey kidnaps and threatens to kill him unless Tharon agrees to marry Courtrey following his divorce from Ellen. Courtrey's wife informs Tharon of Billy's whereabouts, and she rescues him in time to join the townspeople attacking Courtrey's gang. Courtrey is pursued by Tharon, who kills him and returns to become Billy's wife.

In this adaptation of Zane Grey's novel, adventurer Dick Gale (E.K. Lincoln) is traveling through the Southwest. He helps rescue Mercedes Castanada (Margery Wilson) from the clutches of notorious outlaw Rojas (Walter Long). Mercedes' fiancé, Captain George Thorne (Edward Coxen), entrusts her to Gale's care when he returns to duty.