Blanche is freshly installed in Cergy-Pontoise, a trendy new town near Paris. She has a new apartment, a new job with no one over and no one under her. She meets Léa at the swimming pool, and soon she meets an acquaintance of Léa, Alexandre, who she approaches somewhat awkwardly. The movie then follows the time-honored plot of exchange of relationships, as Blanche and Lea switch boyfriends. The title of the movie in French is a pun: The boyfriend of my friend (could be my boyfriend).