A teacher from Pomona, California and two friends are vacationing in Mexico. By lingering too long in a Mexico City gift shop, Jean Harper accidentally gets left behind.
Jimmy Donovan, a lawyer from the U.S., is on his way to Acapulco to handle the divorce of a wealthy woman, her fifth. 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.
Jean tags along on the bike, hearing the kidnap report on the radio but not telling Jimmy about it. When police confront him, Jimmy and Jean pretend to be newlyweds and take the bridal suite when the cops keep observing them. An orphan boy, Juanito, befriends them and wants to be adopted. He eventually gets his wish when Jimmy and Jean straighten things out.
