This drama is like the more unpredictable drama I've ever watched. I like how TvN's drama tends to relie more on the plot than current popular actors/idols to get good ratings. [The Story] So like I said it's the most unpredictable drama I've ever watched. The plot was from the beginning very interesting and creative. Even though the time travel thingy seems to be the trend nowadays, the fact that the main character actually travel back and forth at the exact same time but with a 20 years difference makes it unique. Each episode brings its share of suspense which makes you fall down from your chair and even though there are only 4 episodes left, I still don't have a clue about what the ending could be like. [The Cast] Even though some of them seem to have a long career, I didn't know any of the actors when I began to watch, and I must say some of them definitly impressed me. Lee Jin Wook (Park Seon Woo) has a lot of charisma, and I think he portrayed his role perfectly. We can also feel that he has a good feeling with his co-actress Jo Yoon Hee (Joo Min Young) and this adds a lot of credibility to the romance part which isn't that big to begin with. [The music and rewatch value ] The OST doesn't appeal to me particularly but it definitely matches the drama well and adds a lot to the sad and suspensful scenes. I gave a 9 for the re-watch value because I'm 100% I'll watch this drama again, just to be sure I didn't miss anything now that I know everything (well, almost, because there are still 4 episodes to be broadcasted) and because the drama really leaves me a deep impression and makes you addictive. In conclusion, if you want to be surprised and like suspens, this drama is made for you :)