West Coast's Walley World theme park is the holiday destination for the Griswold family, who intend to drive cross-country from their Chicago base. Father Clark (Chevy Chase) has planned the trip down to its last detail, but the trouble begins as soon as they hit the road. Unexpectedly forced to share car space with grumpy aunt Edna, and missing out on their chance to see the world's largest ball of twine, their woe is complete when they arrive at Walley World - to find that it has closed down. The Griswolds suffer further holiday nightmares in 'National Lampoon's Christmas Vacation' and 'National Lampoon's European Vacation'.