This series is great for those who enjoy a bit of mystery, action and crime drama. But I would not call it the best in this genre mainly because some themes are repetitive (planting evidence) and the show gets a bit slow and drags at times.

The story revolves around a shady cop, Ryo Soo Yeol, who is known to take bribes and does not care to find actual evidence and criminals. However, his motivation is mostly because he wants to earn money and not because he is morally dead. This is proven when a crazy man, K, appears in his life and forces him to look at evidence in a case and help a rookie cop, Oh Kyung Tae, who has been made the fall guy in the disappearance of a little girl's mom because he saw too much and would not give up trying to find her. From there, K continues to push Soo Yeol into situations that force him to seek the truth and punish criminals even at the risk of his own life.

Eventually the show dives into Soo Yeol's own past and another series of murders that are linked to it.

SPOILER: Although I enjoyed the new take of this show on the inclusion of a character with Dissociative Identity Disorder, the characteristics are more fiction and stretching the basis of how DID develops (aka trauma) and it's presentation. For example, someone with DID can be aware or unaware of a second or other persona(s) but they do not physically see them as external hallucinations. Also, usually one identity is in control at a time rather than simultaneously. There are moments when Soo Yeol is escaping a room full of goons while K is inside still fighting them. Then they were depicted as both fighting different sets of goons which is impossible. There are too many moments which feel supernatural for it to be an actual case of DID so the entire scenario must be taken with a grain of salt.

Overall: The drama is fun. Has elements of comedy. The episodes could have been shorter and the police could have been more efficient. It is enjoyable but ultimately I have to rate it a 7 because of the presentation and content.