Traveling con artist Harold Hill targets the naïve residents of a small town in 1910s Iowa by posing as a boys' bandleader to raise money before he can skip town.

A man is mistaken by foreign agents for a defecting cosmonaut and must prove his identity while evading capture.

Jesse W. Haywood (Don Knotts) graduates from dental school in Philadelphia in 1870 and goes west to become a frontier dentist. Penelope "Bad Penny" Cushing (Barbara Rhoades) is offered a pardon if she will track down a ring of gun smugglers. She tricks Haywood into a sham marriage as a disguise. Haywood inadvertently becomes the legendary "Doc the Haywood" after he guns down "Arnold the Kid".

Jerry Lewis plays Norman Phiffer, a proud man in a humble life, who doesn't know that his girlfriend, Barbara, is heir to the Tuttle Department Store dynasty. Mrs. Tuttle, Barbara's mother, is determined to split the two lovers, and hires Norman in an attempt to humiliate him enough that Barbara leaves him. Will she ruin their love, or will he ruin her store?

Warren Nefron is a hopeless klutz who has some of the worst luck in the world: when he tries to end it all with a foolproof suicide plan, he still manages to mess it up. In desperation, he goes to a psychiatrist to see if there is some way for him to end his troubles.