Alex (Jean-Paul Rouve) feels as if he's sitting on top of the world -- he's enjoying a successful career as a writer, and he's in love with a beautiful woman, Laeticia (Melanie Doutey) who seems to be just as infatuated with him. But as Alex's romance with Melanie progresses, she gently but firmly insists on a more permanent relationship, and asks him to move in with her. Commitment-phobic Alex is convinced this is the first step towards marriage, and insists on keeping his own flat. Running out of excuses, Alex persuades his agent Jacques (Kad Merad) to feign depression and move in with him, but Laeticia isn't buying Alex's angel-of-mercy act and finally lays down the law -- either they move in together or she's going to leave him.
Alex and Laetitia appear to make perfect couple. But, as much as he loves his gorgeous fun-loving sweetheart, Alex isn't yet ready for her to move in with him.