This is one of my favourites. I am thankful to watch Korean dramas of this kind which are not only about love. In this case, suspense plot is what I liked the most. The OST has some beautiful songs too, I especially love "Saranghi Marayo". I really recommend watching this drama, but I think it loses a lot of interest if you rewatch it, because it loses the mystery of the first time, which is particularly important in this kind of dramas.