A cruel but beautiful heiress mocks and cheats a hired carpenter. When she gets amnesia after an accident, he decides to introduce her to regular life by convincing her that they're husband and wife.

John Lefsburg, a small town detective, has lost his will to live. Demoted to mundane duties, he is assigned to transport a homeless man, Simon Applewhite, to a psychiatric ward in the nearby city of Madison. Simon claims that aliens are invading the earth from the moon. His mission is to kill media mogul Frank Coen, who Simon believes is an alien staging an invasion to destroy the human race. Through a series of mishaps, John's and Simon's lives become intertwined and both must help each other in order to reconcile their troubles.