Two American astronomers attempt to warn humankind about an approaching comet that will wipe out life on planet Earth.

World War II soldier-turned-U.S. Marshal Teddy Daniels investigates the disappearance of a patient from a hospital for the criminally insane, but his efforts are compromised by troubling visions and a mysterious doctor.

When car dealer Charlie Babbitt learns that his estranged father has died, he returns home to Cincinnati, where he discovers that he has a savant older brother named Raymond and that his father's $3 million fortune is being left to the mental institution in which Raymond lives. Motivated by his father's money, Charlie checks Raymond out of the facility in order to return with him to Los Angeles. The brothers' cross-country trip ends up changing both their lives.