This is a pretty entertaining French murder-mystery revolving around a series of disappearances of three teenagers in a French suburb, and the effect it has on their group friends. It is not your typical police procedural since the focus is almost entirely on the teenagers with adults largely relegated to roles of potential suspects and potential red herrings. It's not your typical teen movie either (at least in Hollywood sense) because it's more dark and disturbing with more adult content and much more SOPHISTICATED plot. The narrative structure is kind of reminiscent of the 1950's Stanley Kubrick film "The Killing" with the movie going back four different times to show the perspective of four different characters. The narrative threads do overlap in places, but they also act as different pieces of an intriguing puzzle that eventually form a more-or-less complete picture at the end.
The actors in this typically look a little long-in-the-tooth to be actual teenagers. One of the male actors (Arthur Mazet) I recognized from his lead role as the hapless young protagonist in the French comedy "Sea, No Sex, and Sun" and he really doesn't fare any better here. Ana Giradot, who plays the pretty, popular girl, would go on to a young adult role in the acclaimed French TV series "The Returned" (which unlike this movie, is easily available in the US). One of the other major actresses (Selma El Mouassai) is unusual in that she is slightly overweight, and while not necessarily unattractive in reality, is downright hideous by Hollywood and the usual French movie standards. Audrey Bastien, who plays the girlfriend of the missing "Simon" of the French title, is very attractive by ANY standards and I would expect to see more of her in the future.
This an entertaining movie and definitely worth watching. I hope it makes it to the US some day.