I highly recommend this drama! Month after you finish the last episode you will probably consider watching it for a second time.

PLOT:
Interesting story with good balance between dynamic, informational and drama moments. In this drama we see character development, inner persona dilemma and interesting life choices.

MUSIC:
The OST is really good. After the 3rd episode you will be huming the main track.

ACTING:
Hyun Bin - Hyun Bin did really amazing job! There is one scene that totally below my mind. By my opinion he did 90% of the drama.
Park Shin Hye - I really hoped that she will change my bad opinion of her, but it didn't work. Really weak cry and emotional scenes but she did good with the fear scenes.

SPECIAL EFFECTS AND ECTION:
Really good job, not the best but 8 from 10