Saddest kdrama i ever watch.. it was so heart breaking.. i re-watched a lot of times and i cried a lot all the times.. everything was great.. it was lead by great actor and actress as well.. excellent storyline and they developed the character very well.. best OST also.. I really wish that they can make the second part.. at least give Hae Soo and Wang So little bit happy life since they never had one.. You better prepare a lot of tissue when u watch this kdrama..