If you don't have ANYTHING else to watch don't mind getting annoyed by lack of logic in almost every aspect of the plot, hypocrisy of the main leads, doesn't mind the lack of actual mystery(since you can deduce everything from first 2 episodes) and like ghost connected stories- then go ahead and watch this drama. But honestly can't recommend that.

First of all, there are numerous little plot holes almost everywhere through the plot. Starting with ex-detective doing a hearing with a possible serial murderer, going through the unlogical actions of characters(needed to push forward a wreck of the plot since the whole mystery was pretty much obvious since the beginning), ending up with just obvious plot holes making me question why am I even continuing to watch this show (for example, detective get almost killed, the murderer says she will kill her like others- but then when detective arrests her- they say there is no proof???? SHe just attempted to kill someone and confessed to her previous crimes though????).

The answer to that question is simple though- the sole reason that I dragged myself to the end was Popeye- Jo Ha min.
He was an only complexly build and acting fairly logical character in this whole mess of a drama and my heart ached for him.
The main leads on the other hand- oh gosh, it's been long since I last disliked main leads SOOOO MUCH. Their actions and behaviors were just purely illogical and was pissing me off countless time.
I guess the moment I was pissed the most was when the female lead reached the peak of hypocrisy- while calling her "father" who abused kids to the point of them pissing themselves from fear, a "good person" (because he was KILLING AND ABUSING thinking it would bring his daughter back) she treated Popeye- the boy who after losing his alcoholic mother since early childhood was abused, looked at his friends being beaten up, manipulated and just purely robbed from his life-like a literal trash saying "he made a choice to become a monster"?????? Ok if we are heartless and apathetic enough to say that and think it's even remotely true- then what about her father???? And her who also was there and didn't stop anything???
I almost always side with the female lead but this time I kinda wanted to punch her almost whole time...

The male lead too- not minding the woman who sold orphans for organs walking free??? And making plans with her???? What??? And you call yourself a "good detective"????

As I said before- there was no mystery- or more like they acted like there was some while anyone could tell what happened since the first two episodes and all the plot twists were almost forced by a lot of illogical happenings.

Generally- just don't waste your time and nerves, there is a lot of better mystery dramas out there. You may watch it if you really love spirit, supernatural related dramas but there are better ones about that out there. For me the only reason to watch this drama is Popeyes character.