I did my very best to not compare this drama to the original K-drama (Hello Monster). However, the more I watched, the more interesting it became and over time, I was engrossed in it and kept watching forgetting a bit about the original.
Like the story is initially the same, but you know how it is in remakes, there will always be major or minor changes. The changes in this drama were minor so they weren't much of a big deal to me.

For this drama, what rooted me was the actors/characters themselves more so than the story itself. Like I already knew the story, but I wanted to see how the actors would enact the characters and make them into their own version without making me think of the original or try to compare. I wanted them to make me feel like I was watching something brand new. That is what I look for and what I want to feel in remakes when I watch them. I never looked at who were casted and wanted to be surprised(minus seeing Tay in the poster) to see how the characters can make the story unfold and how well they able to interact with each other and make me as a viewer continue to watch. I think they succeeded in pulling me in and making me not wanting to stop watching. It had that effect of making me want to rewatch the original story and not in a bad way or to compare, but just to enjoy its originality and appreciate the efforts of the remake.

It took a while to get used to some of the characters. Like the FL, I couldn't get used to her. I'll be very biased about that with no Fs to give. I don't know why they made her so plain and kiddish-looking and she looked so lost half the time. She didn't even seem like a cop at all. LOL I didn't dislike her but she was my least favorite character. The rest investigation team were cool peep, even the Lieutenant/ team leader was so cute.
Now, for the big 3. Kong, the actor who played him was quite creepy but he didn't give me much chills as I was expecting. Like I felt like he was trying really hard to give off that serial killer vibe but because he was trying too hard, it didn't have much of an impact to me. Paytai, played by hottie Tay wasn't bad, but it felt lacking. I don't know what it was but I wanted him to spice up his character some more. I know he could have because he's an amazing actor but to me, it felt like maybe he was holding back a bit. Now, my fav character was Tanwa/Tony played by Petch. He did well. Something about this guy interest me a lot and he was one of the main reasons why I continued to watch. It was my first time seeing this actor, but I actually really liked how he acted.

The story was decently written and I did enjoy the drama as it's own if I didn't watch the original and I do like it as a remake. I don't care for the music, not that it was there much of the time.
Will I rewatch this? Probably not. These dramas are a one type watch dramas. If I rewatch again, it would be specific scenes, not the entire thing.
Would I recommend this to anyone who has or hasn't seen the original? Sure! I'd recommend this for one who hasn't seen the original. As for those who's seen the original, I'd say this drama wasn't bad at all. Don't pay much attention to anything, just watch of your own volition and judge for yourself whether you will enjoy it or not.