Xavier (ROMAIN DURIS) is a student in France who's decided to participate in the Erasmus foreign study program where he'll complete his senior year in Barcelona. That doesn't sit well with his hometown girlfriend, Martine (AUDREY TAUTOU), but he's soon off to the cosmopolitan city where he speaks little of its native language.
For a while, he ends up staying with fellow Parisians Jean-Michel (XAVIER DE GUILLEBON) and Anne-Sophie (JUDITH GODRÈCHE) who have recently moved there. Jean-Michel is a neurologist and asks Xavier if he wouldn't mind escorting his new bride around the city since she similarly knows no one there.
Xavier does and they eventually become more than friends. Nevertheless, he ends up finding a place in an apartment full of international students that includes English Wendy (KELLY REILLY) and later her brother William (KEVIN BISHOP); Spaniard Soledad (CRISTINA BRONDO); as well as Italian Alessandro (FEDERICO D'ANNA), Dane Lars (CHRISTIAN PAGH) and German Tobias (BARNABY METSCHURAT).
When their landlord raises their rent, Xavier proposes that his Belgian lesbian classmate, Isabelle (CÉCILE DE FRANCE), join them, and soon their apartment is overflowing with people, languages and varied tastes. As the year progresses and everyone's lives unfold and develop, Xavier tries to juggle his classes, living situation, an affair with Anne-Sophie and his long distance relationship with Martine.