Kreton (Jerry Lewis) is an innocent and childlike alien from the planet X-47 who has always been fascinated by Earth.
Eventually getting the opportunity to visit our planet to study the human race, he decks himself out in a Confederate uniform and lands in Richmond, Virginia, to help General Lee’s troops sort out those Yankees – unfortunately he’s 99 years too late for the Civil War.
And so he sets about observing the customs of 20th century Americans, mostly Ellen (Joan Blackman) and Conrad (Earl Holliman), but including a visit to a Beatnik nightclub (called The Hungry Brain) where – amongst other things – he gets to play the drums with Buddy Rich.
Kreton becomes friends with the suburban Spelding family – headed by television presenter Roger Putnam Spelding (Fred Clark) – and stays with them after they agree to keep his alien status a secret. Along the way, he falls in love with their daughter, Ellen himself (despite his race having abolished all emotion).
Repeatedly disobeying his teacher, Mr Delton (John Williams), and his rule against getting involved in humans’ lives, Kreton has all his extraterrestrial powers stripped away so he can discover for himself that being human comes with other, less desired, emotions like pain, sadness, and jealousy.
Once his cover is blown on Earth and he is reported to the police, Kreton decides that emotions are not worth the trouble, so he returns to his own planet.
Based on a Broadway stage play by Gore Vidal.
Maj. Roger Putnam Spelding
Mr Bob Mayberry
Mrs Mabel Mayberry