Orphaned and left in the desert as an infant, Evil Roy Slade (John Astin) grew up alone—save for his teddy bear—and mean. As an adult, he is notorious for being the "meanest villain in the West"—so he's thrown for quite a loop when he falls for sweet schoolteacher Betsy Potter (Pamela Austin). There's also Nelson L. Stool (Mickey Rooney), a railroad tycoon, who, along with his dimwitted nephew Clifford (Henry Gibson), is trying to get revenge on Evil Roy Slade for robbing him.
Slick lawyer Thomas Farrell has made a career of defending mobsters in trials. It's not until he meets a lovely showgirl at a mob party that he realizes that there's more to life than winning trials. Farrell tries to quit the racket, but mob boss Rico Angelo threatens to hurt the showgirl if Farrell leaves him.