Clark W. Griswald, his wife, Ellen, and their teenaged children, Audrey and Rusty, are contestants on a game show called “A Pig In A Poke.” They win the grand prize: a two-week, all-expense-paid European vacation. Audrey does not want to leave her boy friend, Jack, behind. Before they leave, Clark videotapes a provocative striptease performed by his wife. On the plane to London, England, Ellen dreams that she meets Queen Elizabeth and Princess Diana, Audrey has a nightmare of gaining weight from the rich European cuisine, and Rusty dreams of beautiful women fawning over him. Arriving in London, they follow the itinerary provided by the game show, which promises luxury accommodations. However, their hotel room is not up to par. Clark has trouble driving on the opposite side of the road, gets into three car accidents, and is stuck driving for hours in a roundabout. Sometime later, they visit Stonehenge, and Clark reverses his car into the rock installations, knocking them over like dominos, as he drives away. Next, the Griswald’s arrive in Paris, France, and a local man steals Clark’s video camera after he offers to take a family photograph. Clark buys everyone berets with their names on them, and they visit the Eiffel Tower. Later, they race through the Louvre museum in fifteen minutes, and Ellen pleads with Clark to slow down their tour. Audrey is distraught when she receives a break-up letter from Jack. The family drives to Germany to visit Clark’s distant relatives, Fritz and Helga. They arrive at the wrong home, however, and fail to realize the elderly couple are not Fritz and Helga. The German couple do not speak English, but welcome the Griswalds to dinner, and allow them to spend the night. The family leaves the next day, thinking they had a nice visit with their family. At a German festival, Rusty meets a local girl named Claudia. After kissing her, she shows him her breasts. Elsewhere, Clark wears a Bavarian costume and joins performers on stage where he participates in a traditional dance. Clark accidentally incites a riot, and the family flees as an angry mob pursues. They board a train for Rome, Italy, but lose their luggage in the process. Meanwhile, two criminals hold up a Rome traveler’s check office, and tie-up the shopkeeper. When Clark arrives to reclaim his lost traveler’s checks, the criminals pretend they work in the shop, and give him three times the amount he lost. Additionally, they provide him with a rental car, in which they have hidden the shopkeeper in the trunk. The thieves secretly follow the Griswalds around Rome. The family buys extravagant Italian clothes, and later, the teens demand some time away from their parents. Ellen sees a billboard with a suggestive photograph of her on it, and realizes it came from the stolen video camera. She is furious with Clark for not erasing the provocative videotape as promised. The family goes their separate ways, and the criminals follow Ellen, who drives off with the hostage in the trunk. Elsewhere, Rusty meets an American girl, while Audrey attempts to purchase a ticket home to salvage her relationship with Jack. Meanwhile, Ellen proceeds to get drunk at the hotel bar, and is joined by one of the thieves, whom she recognizes from the travelers check shop. Believing him to be the shopkeeper, she regales him with her marital woes. When she goes to her hotel room, the man follows, and tries to seduce her. Ellen fights him off, and picks up the telephone to call police, but he holds a gun to her head and kidnaps her. As the thief escorts her out of the hotel, Ellen sees her daughter in the lobby, and throws her the keys to the car. Audrey realizes something is amiss, and when her father arrives, they chase Ellen and her kidnapper. Clark and Audrey race through the streets of Rome. As Clark crashes along the narrow streets, he sees Rusty and his new girl friend, who get into the automobile. When he gets a flat tire, Clark opens the truck and finds the bound shopkeeper inside. In mid-pursuit, Clark takes a nearby bicycle and chases after Ellen. He jumps into the convertible and the kidnapper crashes into a fountain. Ellen embraces Clark, and the Griswalds happily return to America.