When Michael O'Brien and his father, James, buy a new car just in time for the family's summer vacation, James signs over more than the title to his old AMC Gremlin in his rush to buy the brand new Inferno station wagon. Joining them on the trip are Michael's creepy younger siblings, Elvis and Olivia; his overbearing mother, Mary, and her pet Chihuahua, Lucky; his backwoods aunt, Margie; and the cremated remains of his grandmother, June, whose dying wish was to have her ashes scattered in th ...