As someone who doesn't even watch a lot of K-drama, and is normally hard to impress, this one is definitely the kind of series that makes you feel as though you cannot watch another drama and enjoy it just as much again. It is just *that* good.
The first episode may seem as though its story is pretty generic, but trust me when I say that it only gets better. So much more happens later on in the story. Even though I have already completed this series, I still wonder how they were able to escalate the story with perfect pacing in just 20 episodes.
Every review that rated this series a high score is completely reliable. It is seriously not your typical K-drama, and it will definitely leave you caring for more than just the "romantic" aspect of the series, even if that is what you came for. I assure you that there is no boring or unnecessary side story nor side character, as you will find that everything is all relevant to each other. The characters are written in such a human way, so if you are into three-dimensional characters, you will definitely find yourself completely attached to a lot of characters (not just the main ones). The story is extremely well-written, and there are definitely no "skippable" parts in the series.
However, one thing I would SERIOUSLY suggest for you first-time watchers is to NEVER SEARCH THIS DRAMA UP elsewhere because chances are, YOU MAY FIND SPOILERS.
I was able to enjoy this to its maximum potential because I was completely spoiler-free! So please, save yourself from destroying your own experience because it is truly a much more magical adventure when you do not completely know the direction of where the current episode is headed.
Trust the words of us reviewers, but enjoy the show under your own experience. All we reviewers can say is that it is truly worth its hype, and you will find out why so many international watchers wished it deserved more attention in Korea.