A stranger is caught cheating in a game of Five Card Stud in a Rincon, Colorado, saloon in 1880. Van Morgan (Dean Martin) unsuccessfully tries to save the gambler's life as the other five players lynch the cheat. Meanwhile, a gold rush has brought a group of outsiders to Rincon, like gun-toting preacher Jonathan Rudd (Robert Mitchum) and Lily Langford (Inger Stevens), with her collection of beautiful lady "barbers."
When two townspeople are murdered, Van remembers that both victims were playing in the fatal card game. Tension mounts as the killer stalks the other players until, at last, two of the principals confront each other and, with a showdown gunfight, the case of the Five Card Stud game murders is closed.
Ray Gaulden's novel comes to the screen in this western murder mystery. In a small Colorado town, a man is caught cheating in poker game and is promptly lynched. The town then falls into a panic as the five members of a lynching party are murdered, one by one. Dean Martin leads the cast, which features a menacing Robert Mitchum as a mysterious fire-and-brimstone preacher.