This movie questions the authoritarian role of a director while making a movie: the control over the story, the actor, the viewer... Pérès is smart enough to look into every aspect of the making of a movie and brave enough to show what is usually hidden in films and to withdraw what is usually shown by other directors. That's probably why he plays in the film, to let the viewer observe the whole experience and make up his/her own opinion about this movie and about cinema.
This is not an entertainment and you need to forget what you usually expect to enjoy this movie. If you don't like that kind of movies, don't watch this one, and if you watch it by mistake, perhaps you should take a moment to think about what you saw before sending your comments to IMDb...