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 American Old West", so he's thrown for quite a loop when he falls for sweet schoolteacher Betsy Potter (Pamela Austin). Nelson L. Stool (Mickey Rooney), a railroad tycoon, along with his dimwitted nephew Clifford (Henry Gibson), attempts to get revenge on Evil Roy Slade for repeatedly robbing him, and sets out to hire legendary retired singing-sheriff Marshal Bing Bell (Dick Shawn) to bring Slade to justice.