A well made revenge thriller, with particularly gruesome and graphic retribution acts. I'm not really into it with this level of nastiness. If you want a good feeling in you after a viewing, don't see this.
Though by the end, the aforementioned excessive nastiness can be explained by a story revelation, there's still not much gain from this given the negative prestige we feel for the main character.
The film-craft is in top form here with a high level of art attributed to the script, direction, acting and sound. Unfortunately the main character is an awful person, even before he went evil. It's not easy to sympathise with the guy, for his gruesome acts and short flashback segments which don't display his humane side for long enough. Not possible to get close enough to him.