Absolutely loved this drama! This was a very unique and cleverly written drama, I've never watched anything like it before. I was hooked from start till end. It is an alluring, mystical drama which reeked of darkness, and the visual effects and OST in this are superb. I absolutely loved every OST in this drama and i am still hooked on it.
The director selected casts that really suited the characters and managed to portray the characters well. I think that that is what really made it for me.
At times however, there were way too many flashbacks i.e. the FL always had this same flashback over and over again. I guess they were trying to portray her sadness but after the 3rd same flashback, I was over it.
I hope there is going to be Season 2 because there really would be potential for a season 2! Although, the ending was amazing.

Overall, highly highly recommend. High emotional impact. Great director and cinematography. One of my all time favourite dramas.