Homer Flagg is a railroad worker in the small New Mexico town of Desert Hole. One day, he finds an abandoned automobile at an old atomic proving ground. His doctor and best friend, Steve Harris, diagnoses him with radiation poisoning and gives Homer three weeks to live. A big city reporter hears of Homer's plight and convinces her editor to provide an all-expenses paid trip to New York.

Jerry Lewis
as Homer Flagg

Dean Martin
as Dr. Steve Harris

Janet Leigh
as Wally Cook

Edward Arnold
as The Mayor of New York

Fred Clark
as Oliver Stone

Sheree North
as Jitterbug Champion

Sammy White
as Waiter

Sid Tomack
as Master of Ceremonies

Sig Ruman
as Dr. Emile Egelhofer

Richard Loo
as Dr. Lee