I started watching this drama after I saw the INCREDIBLY creepy stills of Lee Joon as a clown- around episode 4. From the beginning, this drama both terrified and delighted me. The storyline was generally fantastic- every episode had me on the edge of my seat, unable to stop watching, and I couldn't wait for each episode to come out. I hate horror/scary films, but this one I thoroughly enjoyed. Towards the end, the storyline didn't have the same shock factor that the first fifteen did, but it is certainly still VERY well written with loads of plot twists. I thought the ending was very fitting. It is a fantastic, chilling mystery show. The cast were superb but Lee Joon outshone the rest of the cast. This show- in my opinion- wouldn't have been as good without him, and I'm looking forward to what he does next. The last show I saw Kim Ji Won in was the Heirs, so I pleasantly surprised by how good she was in this. Yoon Sang Hyun- brilliant as always- and Kim Min Jung were a great duo. It was really well cast. The music was good- I particularly liked the theme song 'Rush' by Every Single Day, I sang along to it every episode. I really loved this drama, and I am going to rewatch it :D I absolutely loved watching this drama, and I cannot recommend it highly enough- it has been the best drama so far this year! :D