The fourth and final film in THE MAGNIFICENT SEVEN series... The leader of the "Seven" (Lee Van Cleef) is now married and settled down as marshal of a small town. When a psychopathic teenage killer robs a bank, wounds Van Cleef and then kidnaps, sexually molests and kills his wife (Mariette Hartley), Van Cleef's "peaceful" life is destroyed. He accepts a new "mercenary" assignment: to protect a small Mexican town from a vicious gang that has already killed all the men in the town. Van Cleef recruits five convicts (Luke Askew, Pedro Armendariz, Jr., William Lucking, James B. Sikking and Ed Lauter) to help him, plus a newspaper reporter (Michael Callan) who wants to write his story. Among the distressed women welcoming the guns of the "Seven" are Stefanie Powers and Melissa Murphy. Music by Elmer Bernstein.