I read that there are a lot of good and bad reviews for this drama. In my opinion it is just that you have to be a little bit in the mood to watch it, and not hoping for something too happy. It is a dramatic drama, and the main topic is not the girl; "is she died or is she still alive?" is not the main question, the main question is "what happened to HIM? how will HIM fight the situation?" That's all. I think people misunderstands since the plot is full of mistery, so they focus on the wrong elements. The story is nothing much, just a lack of memory and then the main guy who can remember again. It is good because is filled with mistery, good characters and places (the Lupin thing is just "OMG this place and this thing is so good!"). It is enjoyable but I have to say to me it is more like an introspective view in the difficult life of someone who is living without knowing an important part of himself. Speaking of the casting, I liked it. I remember Changmin in Paradise Ranch, and I have to say he improved a lot. In this drama he was very "pokerface", but it was so much in his character. His expression, even though it was the same all the time, was full of feelings. When he cried I felt like crying too. He wasn't fake at all. He was just in his character. The same thing for Mimi. The actress made a good job with her character, because from the beginning till the end you could see the differences between them and the importance of her personality in his life. A thing I liked but not so much, was the music. Even though it was good, it wasn't the best for the drama. But it is only my opinion. Overall, I think it is a good drama, good to watch if you feel like "oh, I have nothing to do and I am in the mood for something depressing."