The Daytrippers

Eliza finds what seems to be a love letter to her husband Louis, who's working as a publisher in New York City, so she decides to go to the city and confront him. Her family, including her sister, Jo, and her fiancé, Carl, as well as her parents, Jim and Rita, go along for the ride in the family station wagon from Long Island.

The movie provides a very entertaining look at family relationships, and has a surprise ending.