Ending bothered me *Spoilers*

That bothered me a little but then I realized he was thinking of the affect on the KILLER knowing his family (especially his son) were to cause, witness and then live with his death.

Something people seem to consistently fail to grasp about this film is that the protagonist is not Superman. He doesn't have some comic book character code of morality which prevents him from doing anything other than slapping cuffs on mass murderers. And he is not a "Hollywood" hero cop either. The things that he does in the film aren't necessarily supposed to be "feel right". Though I can certainly understand where his character is coming from.

Soo-hyeon is a man possessed by vengeance. His entire life was destroyed in one moment and it sent him off the edge. Yes, he's reckless. That's part of the movie and his character. It is consistently acknowledged by other characters in the film. His loss was too great, it broke him.

He sets up the final scene precisely because the only thing in the world that matters to him any longer is inflicting pain on the man that killed his fiance and his unborn child. I thought he was going to murder Kyung-chul's son in front of him to replicate the sense of loss. It would have justified the film's title (and controversial reputation). What Kyung-chul got was a different sort of torture, but it was clear that he finally panicked in that moment and knew fear. He fought with everything that he had to prevent his death, despite having brazenly invited his hunter to kill him previously. Soo-hyeon wanted him to fear death and to know pain. We don't get an internal monologue explicitly stating that the guillotine setup succeeded in that way or anything, but it sure seems like he got the desired effect in the end. The thought of Kyung-chul's decapitated head enjoying its last few seconds of consciousness, rolling on the ground and hearing the screams of his family, was probably sweet music to Soo-hyeon given his disposition by the end of the film.

I thought it was superb and tied right into what the cop told him. I'll kill you when you are at your weakest and in the most fear and pain and so we see this obvious sociopath in real fear when he hears his son and the old folks at the door and begging them not to open the door. Begging for his life......................Priceless!!

It will haunt them for the rest of their lives.

I think that's why the agent cried at the end. Not only release, but he knew that he achieved another aim: To inflict the same pain on the killer's family as he had inflicted on the girls' families.

I thought, too, maybe the killer's parents had some guilt to bear also. That maybe some things they did to the killer as a child - and maybe too to his son, created the monster. Remember the grandfather/father's attitude at the beginning?

Scary and thought-provoking. and Choi gives another great performance.