Story:
If you love watching time travel, sci-fi kind of drama then you must watch this drama. It is not a perfect plot though, there's some holes in the story and illogical scenes but still this drama gave me full of excitement, curiosity and all kinds of emotions from ep.1 to 16. I love that it has a clear lesson to convey to the viewers, - "don't dwell on the past that cannot be undone, appreciate more your present time and the persons around you." If you're a person who keeps turning back on your past, this drama might help you to get some realization.

Acting/Cast:
Perfect 10 for the main role especially to Joo Won and Kim Hee Seon. As always, you will never disappoint in their acting.

Music:
All OST are all good, but some of it are not my type of music.

Rewatch Value:
If I will miss watching Joo Won I will watch it again. I actually watched the first half 3x.