One reviewer states that their are undertones of "Seven" in this movie and I think that's an understatement. This movie has the dark mood, vengeful plot, and murky lighting of "Seven," but is not nearly as good.
I will first acknowledge that I have never been impressed by Angelina Jolie, but it was this movie that really made me unimpressed by her and gave me reason to wonder about the otherwise redoubtable Denzel Washington too.
This is a dark, grotesque movie, with unrealistic and stagy murders. The denoument is a joke, with a character that probably had five minutes screen time in the film as the killer. By the way, the clues to who the killer is are all in the opening credit sequence, something that I find annoying in the extreme. You should not miss out on a what is apparently a crucial part of the film just because you had to wait in line for popcorn.
I am saddened that I spent any money at all on this film (at least I went to a discount theatre). If you must see it, rent it, don't buy it. You won't want it sullying the rest of your DVD collection.