Honestly I would say, one of the most underrated K-Dramas I know.
I honestly thought, it was pretty good because it had so much, like fantasy, thriller, crime, romance , psycho, law and so much more. There was so much depth behind all their stories and like some wtf -moments, for example when we found out, that Kim Sungmo and his mother were kidnapped and she was r*ped there, so he grew up in a basement. Also the perpetrator was so sick and his story as well, as being kidnapped and being selled too. Like the whole story were so psycho, and even Lee Ahn whose parents died in the fire and all the murder which happend in such a cruel way. I don't know if some people really grabed the story.
Also the actors were kind of great and i don't know but I think, Park Jinyoung is one of the greatest idol actors out there, like he proved that some idols can really act. I think, he is really good in acting with his eyes and even now I would count him as a real actor. I mean, he is still growing but for his first drama, where he was playing the main role, it was really good.

My only problem was that it was only really thrilling at the second half of the story. In the beginning it was often very lengthy and sometimes it was taking too long to go through a episode. But nevertheless I liked it, also the idea behind it, that someone has psychmetric powers.
The OST's were good, I liked "Take" by JUS2 very much.