Historically the French are the one group of filmmakers who have revered Alfred Hitchcock the most, and as such it is no coincidence that almost every French film that fits the thriller/pot-boiler/tense drama mould has the word "Hitchcockian" used to describe it. In Mark of an Angel (which is based on real events) there are moments that recall the master's handiwork, but the apprentice, director Safy Nebbou, has not quite yet learnt how and when to use the tricks.
The story begins following Elsa, played by the divine Catherine Frot. She has a son, is in the process of divorcing and works as an assistant at the local pharmacy. One night she picks up her boy from a birthday party and sees a little girl, whom she is captivated by. Elsa then pumps her son for information about the girl, Lola, and eventually goes to the school she attends and follows Lola's mother (played by Sandrine Bonnaire) drive them home. After that she engineers a "coincidental" meeting and the obsession takes hold.
Frot and Bonnaire are two of France's finest, and most underseen actresses internationally, so having them paired together guarantess a level of quality. Frot is superb as the unhinged "depressive" woman who fixates so intently on this girl, and Bonnaire gets better and better the longer it goes as the role demands more and more. In a way it's similar territory to I've Loved You So Long, but here there are two finer actresses giving a pair of superior, more restrained and natural performances, so it is a cut above the norm in that regard.
This is not to say Nebbou's film is without flaws, for example there is one tense scene which is revealed to be a dream sequence and from then on out Nebbou cannot escape the confusion created as they never show another dream but it just makes the later moments lose their tension because it's expected that someone will jump out of their slumber at any moment. There are also some fridge logic-plot holes that The Dark Knight would be proud of and even when the characters question how something happened there's still no answer for it, it's not the greatest piece of cinematic writing.
So a stylish film (with one set piece at the ballet that catches the eye in particular), which is impeccably acted, but tries a little too hard to manipulate the audience and comes unstuck in the process. It's a case of the screenwriters trying to do too many things as with the ill-advised dream sequence they put in, they did so for the subtext of one character having to reveal themselves, but it is simultaneously too obvious thematically and also too clunky in terms of the style of the storytelling. Coupled with that, Nebbou's direction is unable to smooth out the kinks so what remains is an interesting, more than worthwhile and certainly good film, just one that could have been quite a bit better than it ended up being.