From start to finish, this drama is solid. No waffling! The drama is really one of the best when it comes to depicting the serious content. It never felt like it was trying too hard to make me feel. It was simple but effective. I liked that other characters had strong deductive reasoning as well. It's not all about the god-like Professor Bo. The plot has a twist! How I love twists. The lead up to the ending is really thrilling. Oh so good. Jin Yan “Are you using Li Xun Ran's life to gamble with me?” “Analysing the mind of a perverted madman is my job, not a gamble.” I think this is the first time I was convinced that the hero wasn't necessarily trying to be mean, he was just speaking his mind. Jin Yan is very direct. He is not good with people. I like that he's not picky about cleanliness or order. Most of the time, characters with his type of personality will be meticulous and OCD, but that's not really his thing. Jin Yan's straight face is actually quite comical. The actor makes use of body language to give his character a lot of personality. His forwardness means he can ask questions that progress the relationship along quicker but as the viewer you're not really sure what it means that he's asked. He also has a bit of a naughty side that he delivers so deadpan I can't help but laugh. “You kissed the President?” “Yes. During the climax of catching the criminal, I went out of my way to kiss my own sister. Are you thinking that I left my IQ and morality behind?” Jin Yan is such a great character. It's hard to describe him. He is stiff, but never boring. He cares but is never kind. He's blunt and a little mean but not rude. He is open to learning more about “normal people” but on his terms. His progression into a human is really subtle and fabulous. I loved the unraveling of his personality. He smiles a lot to himself which makes him more accessible. He's not a diva. I think the interesting thing about him, is that most Korean heroes have the two sides to them, but for Jin Yan, even when he is acting cute, he is still intimidating and even when he's humbly following instructions. I like that he doesn't think he's a monster. That he knows full well who that title goes to. And the drama also emphasises how he doesn't identify with the murderers. That even though he understands them it's because of talent not because of some sinister connection or that there's something wrong with him. Romance This is probably my first time that I swooned over the heroine's romantic lines rather than the hero's. But Yao Yao's beautiful delivery was really touching. Jin Yan is pretty much always respectful towards Yao Yao which is something you can't say of many heroes. And I like that he appreciates her intelligence and seeks out her input on the cases. The pair have a very functional relationship right from the beginning. Their dynamic is really enjoyable. I liked the flirty undertones and how Jin Yan really conveys his admiration for Jian Yao. I love that in a hero. He trusts her. As the drama goes on, he becomes more relaxed and funny. However, when he really starts to pursue her, I found the romantic activities a little jarring. It was almost like he had no heart in it, but rather was using formula as a means to an end. However, once they get together, the drama moves away from focusing on their relationship. I was glad for that because romantic Jin Yan is kind of creepy. Zi Yu Zi Yu at first seems like the stereotypical sidekick. He's a good sidekick. He knows Jin Yan's quirks well. I love the little conversation he had with Yao about his best friend. “His emotional intelligence is basically zero.” He has some really awesome moments when he's got Jin Yan's back. Jian Yao This heroine is amazing. She's very firm right from the start. Unafraid to be a little rude but isn't bratty at all. She doesn't fall for any of Jin Yan's games (not that he plays a lot) and she can give him a fine and sophisticated setdown. As one of the characters says, Jian Yao is both book smart and street smart which is refreshing in a heroine. Despite considerable desensitisation to serial killer plots, I was terrified right along with Jian Yao. I felt Jian Yao's horror towards Jin Yan but similar to her, also felt the curiosity of the mystery and the intrigue of the hunt. She's efficient and capable. Towards the second half of the drama, her character sort of withers away. She doesn't become annoying, she just becomes very unimportant to the plot. It's been a while see a drama really gripped me. I was looking for a drama that would cheer me up and was trying for all the comedies, but nothing worked like the satisfaction of a good drama regardless of genre. P.S. The book that this drama is based on is really good. You can read how Fu Zi Yu and Jin Yan become friends. It's awesome.