PLOT: I just love the story plot and how those mysterious jigsaw puzzles are being solved in each episode, and there finally, the puzzle is formed. I also love how the writer gives each personality a role and purpose of being created - I just love every single personality! CAST: Everyone is really great in the show but I am really amazed by Ji Sung's acting skills! Didn't expect him to portray very well not just one role, but all the personalities! He really should deserve at least an excellence award for this year's drama awards! Furthermore, if you watch some of the behind-the-scene cuts, you will find out that he actually directed some of the scenes himself, which is totally unscripted at all - this makes me respect him as an actor more. MUSIC: I rated high because the OST Auditory Hallucination attracts me ever since the first episode and till the last episode, I am still loving the song! Just love how the soundtrack suits those scenes when it is being played! However, I was slightly disappointed of the other soundtracks because they are only so-so. So yup, there isn't anything much that I am disliking about this drama, except for the ending which I am doubtful if I should be satisfied about it. And I really learn something in this show - to be brave and overcome our fears no matter what. But really, a worth to watch drama overall! It can just bring you laughter, keeping you in suspense, as well as sadness!!