The Science of Sleep (2007)

While slumbering, he is the charismatic host of "Stephane TV", expounding on "The Science of Sleep" in front of cardboard cameras. In "real life", he has a boring job at a Parisian calendar publisher and pines for Stephanie, the girl in the apartment across the hall. While Stephanie is initally charmed by Stephane, she is confused by his childishness and shaky connection to reality. Unable to find the secret to Stephanie's heart while awake, Stephane searches for the answer in his dreams.

Official website: http://wip.warnerbros.com/scienceofsleep/