Overall impression: Interesting plot, but not the most original. Amazing Kim Jae Wook and So Yi Hyun acting. Seriously if you're not Kim Jae Wook fan already you will absolutely fall in love after seeing this drama!^^ Although Taecyeon is cute but I'm still in Kim Jae Wook team;)) Not a best choice if you're looking for something cheerful, it's definitely not in that category. Weekest point: music I started watching "Who are you" while watching Master's sun and everybody knows how amazing Master's sun was so it's difficult to get a very good impression of something with kind of similar plot. I was really interested in the story for the first 8 or 9 episodes but after that story line and romance just got a bit boring. I wanted to finish it after 3 or 4 months of break and the only impression I had about this drama was that it had one good kissing scene (Yang Shi Ohn and Cha Gun Woo) and a ghost that leaved a huge impression. And that's probably because of Kim Jae Wook that I watched this drama to the end. Somehow his sad eyes and his expression were so heartbreaking that I just felt uneasy and wanted to see how it would turn out. So I think that all the glory for this drama still leaving a good impression on viewers despite many lacking points should go to Kim Jae Wook. If it wasn't for his amazing acting it wouldn't be that unforgetable. And when it comes to week points, for me the weekest point of this drama was music. I've been wondering for quite a lot of time why I cannot watch this drama to the end and I've figured out that it's not necessarily because of bad plot or lack of chemistry between main leads. It was because of music. It made whole drama so gloomy and I don't want to say that it shouldn't be that way cause it's still a ghost story but honestly if the music was just a bit more epic in the moments when it should be and more romantic when the scenes required it, some really nice scenes wouldn't be wasted. Music is so important because it brings up emotions and it makes a lot of scenes more memorable but 1 or 2 good songs are not enough to make you keep watching. But still it's quite worth watching, but I don't recommend you to watch it at the same time as dramas with similar plots.