One wonders why this picture was made at all : the plot as such is totally unbelievable if not ridiculous, the characters (experienced loner cop versus younger one, quite fascinated) quite predictable, the ending totally murky and impossible to understand (maybe after several viewings but you'd have to have a masochistic tendency for that ; the idea being you have to read the book to understand fully what it's all about)and the acting is bad. Was the basic idea to show that French film makers are able to do as well as Americans in the genre that include "Seven" and "Silence of the lambs" ? If so, it is a total failure. It was quite a success though (and has a sort of cult-status as the first French serial killer film)and, it seems, considered as a good product to export. Strange.