In order to get to know his two French collaborators better, Henry Wydmark, director of a large American company, invites them to spend a weekend in the Alps. They consider this trip to be part of their job. But as the wife of one and the husband of the other are not free, they do not hesitate to leave their "heart under the mat" and hire one a husband of convenience and the other a wife fictitious. This misunderstanding will trigger a cascade of disasters.
Genial, bumbling Monsieur Hulot loves his top-floor apartment in a grimy corner of the city, and cannot fathom why his sister's family has moved to the suburbs. Their house is an ultra-modern nightmare, which Hulot only visits for the sake of stealing away his rambunctious young nephew. Hulot's sister, however, wants to win him over to her new way of life, and conspires to set him up with a wife and job.