I am sorry but I think this drama is overrated. I know most of people are giving 10, so I thought it was importante that I post a more critical review. Please don't hate me! Yes the actors are good, the cinematography is great and the music also. There is clearly a big budget and the special effects are awesome fo a tv drama. But despite all of that, even if the main plot is interesting, the rythme is extremely slow and all of each episodes are flashback scenes over and over again. I found myself nearly sleeping while watching this. And I do not like the main couple (the 2nd one is really touching on the other hand). Why? Well in my opinion the age cap is too much (not the actors but the characters in the way they are written), she is speaking to Gong Yoo like he is her father and she is acting really like a teenager, I found this disturbing. Conclusion, yes it is a good drama but for me the lack of action and the slowness of it is not compensated by the rest of the positive points.