One Big Affair is a 1952 American comedy film directed by Peter Godfrey and written by Leo Townsend and Francis Swann.

The film stars Evelyn Keyes, Dennis O'Keefe, Mary Anderson, Connie Gilchrist, Thurston Hall and Gus Schilling.

By lingering too long in a Mexico City gift shop, Jean Harper accidentally gets left behind.

He decides to ride a bicycle from Mexico City and ends up encountering Jean, whose friends and tour guide fear she's a kidnap victim.

When police confront him, Jimmy and Jean pretend to be newlyweds and take the bridal suite when the cops keep observing them.