The movie is about a road trip that goes horribly wrong. Brian Kessler (David Duchovny) is a journalist determined to make a book about serial killers, and also wants to move to California with his photographer girlfriend Carrie Laughlin (Michelle Forbes). They decide to do both at once, by driving to California and visiting infamous murder sites on the way. To subsidize the trip, they take on a pair of travelling companions - Southerner Early Grayce (Brad Pitt) and his child-like girlfriend Adele Corners (Juliette Lewis). While the two couples at first attempt to get over their obvious differences with each other, their trips to murder sites become progressively more eerie, particularly when it is revealed that one of the four is in fact a serial killer.