Teddy Duncan's middle-class family embarks on a road trip from their home in Denver to visit Mrs. Duncans Parents, the Blankenhoopers, in Palm Springs. When they find themselves stranded between Denver and Utah, they try to hitch a ride to Las Vegas with a seemingly normal older couple in a station wagon from Roswell, New Mexico. It turns out that the couple believes they are the victims of alien abduction. The Duncan's must resort to purchasing a clunker Yugo to get to Utah, have their luggage stolen in Las Vegas, and survive a zany Christmas with Grandpa and Grandma Blankenhooper.
An aspiring recording artist, Adam, is burned by a bad relationship experience and decides that if women won't respond to the "nice guy" then he'll be "the jerk." This is wildly successful with meaningless relationships, but when Adam meets and falls for Molly, who doesn't fall for his jerk routine, Adam is forced to reconsider his dating philosophy.