What completely ruined this movie for me

a) The casting. The leads are way TOO old to make this thing credible and enjoyable.

It's one thing to watch young people playing games, or behaving in a way as inmmature as mysterious, intriguing and particular, and a very different thing to watch YOUNG ADULTS behaving like inmature, stupid and annoying persons (precisely because you judge their actions differently). I didn't get any kind of sympathy or interest for the leads, because they didn't seem real.

Take the very first scene: students after class. All young ones, 13 to 17 years old... and then Paul appears. You may think that he is a YOUNG PROFESSOR !!!. Only, he is dressed as a student. He`s supposed to be one of them. Too much for a good first impression. (I seem to remember that he's suppossed to be 16 years old, not the 25 years old that he really is and looks in the movie). This anacronism goes for Nicole Stèphane, although in a lesser degree.

b) The robotic narration. I know it's a subjective thing, but a little more of expressiveness and intonation wouldn't have hurt.

Also, I don't think the narration was completely welcomed everytime. Being a different vehicle of expression, in movies narration is something that should be reduced to the minimum. Sometimes, not being able to represent something cinematically, but through narration, seems a cheap trick for a director. Other times, directors have to accept the fact that you can't really represent accuratelly something that is in words, and you really don't need to. After all, people are watching a movie, not reading a book.