Gap Dong is an interesting, suspenseful, and well written story. I like exploring the mind and why criminals do the things that they do. Is it nature or is it environmental? Can anyone at any time become psychotic if they go through a trauma? I watch a lot of crime shows and they always talk about the psychotic break that causes people to commit crimes. The reason why I didn't give it a higher score is because I figured out who the real Gap Dong is almost from the beginning. Also, did you know that in Korea the way to find the "bad guy" is to find the person dressed all in black with a black ball cap? Keke Anyway, the story is good and it ended well. Yoon Sang Hyun was excellent as Ha Moo Yeom. His emotions were written all over his face and I think that is the sign of a great actor. I have never seen Kim Min Jung in anything other than this. I don't think she is that great of an actress. She seems to have the same expression for every emotion. I thought it was interesting that she acted better when she put on her costumes. Maybe that is the point of her character. Lee Joon was surprisingly good as Ryu Tae Oh. His cold stare turning to a smile was eerily convincing. It gave me the heebie-jeebies. Kim Ji Won as the innocent and well-meaning Ma Ji Wool did a good job also. I felt really sorry for her character. She wanted to see the good in every one. Her character shows how life can cause people to become jaded. I mean how many times can a person get hurt before they start to look at every one with suspicion? All of the other actors are good also. The music is good. I might rewatch this at some point. If you like suspense and crime dramas, then I think you would really enjoy this. It has a little love story in it too.