This is one of the best shows I've watched and will probably be one of my all time favorites.
The story is amazing, gripping, witty and satisfying. There were times when the villains were too annoying but that's what they are there for.

The acting/production is flawless.
Jisung is SO. FREAKING. GOOD. And so very handsome.
Kang Yohan is such a complicated character, and even while I was watching I didn't know if he was good or bad or even sane, but he was all that and more. And Jisung nailed it. Bravo.

The only thing: I WISH K HADN'T DIED