Nick Kegan (Jeff Bridges), half-brother to assassinated U.S. President Timothy Kegan, is pulled into a conspiracy 19 years after the event when Arthur Fletcher reveals he and another gunman were hired to kill President Kegan in 1960. Nick's father Pa Kegan (John Huston) initially dismisses the claim but eventually pledges to help solve the mystery, leading him on a wild goose chase through Philadelphia, Cleveland, and New York City as he encounters a series of characters who offer conflicting narratives about the assassination.