I had mixed feelings on this film
When I walked out of the theater
I had a physical reaction to it.
First, it was difficult to "reconstruct" due to the backward telling of the story, much like the more popular "memento" which I found much easier to reconstruct.
Second, the violence, was palpable and left a sickening feeling, and the randomness of it all. too.
Third, Monica Belucci, is absolutely, breathtakingly beautiful in the movie.
I found it to be one of the 'most powerful" films I have ever watched,
but I am unable to recommend it,
I think it is not possible to watch without being "harmed" in some way.
with that said, I do not regret having viewed it.