I'm writing this review because all the other reviews are extremely positive and feel biased.
I watched this after expecting something as good as Goblin because of what some people implied, which is why it bothered me so much that I had to write a review.

This drama did such a fine job connecting all dots to make sense, I loved it. It really made everything realistic and sensible. Each of the characters had a role to play that we slowly learned episode by episode, until the last 15minutes of the final episode. Suddenly, everyone had to make their own speculations on what happened. It still is so confusing even after reading what others THINK happened, because the drama did not clarify at all.
Really put me off and I was going to give it a very harsh rating, but then I remembered the acting and the music were so well done it was unfair.

So here we go, this is my critical review, 7.5.

P.S: I'm not a fan of typing a 3 pages essay to review anything.