Rent Youth in Revolt (2009)

Michael Cera stars as cool but geeky "nice boy" Nick Twisp, whose life is turned upside down when he meets Sheeni, the girl of his dreams on family holiday. But family, geography and jealous ex-lovers conspire to keep these two apart. Whit Sheeni's encouragement, Nick develops a rebellious alter ego: Francois. With his moustache and aviators, dangerous Francois will stop at nothing to be with Sheeni, and leads Nick Twisp on a path of destruction with unpredictable uproarious consequences.