Jesse Haywood (Don Knotts) is a bungling dental school graduate from Philadelphia in 1870. Upon his graduation he heads west to help the people out west overcome their oral ignorance. Meanwhile Bad Penny Cushing (Barbara Rhoades) is a stagecoach robber given a shot at redemption for tracking down a ring of gun smugglers. To bring about this end she meets Haywood and tricks him into marrying her, using the marriage as a disguise for her efforts. When Haywood inadvertently guns down the bad guy 'Arnold the Kid', he becomes a reluctant celebrity crime fighter known as 'Doc the Haywood'. Unbeknownst to him, and everyone else for that matter, Penny is really behind his exploits.