So this was basically "the" drama for me as after watching this I knew I'm sucked into the drama world!!
The story was quite intriguing from the get go, romance was ADORABLE and that dash of mystery really kept things interesting throughout its course. Also, the fact that there was little to no 'second lead syndrome' was very well appreciated.
Now for each category:

STORY:-
As I've already said, the story was quite interesting and it's unlikely for you to get bored at any point of this drama. There were a lot of characters (like A LOT) and multiple sub plots, which could have ruined the watching experience but luckily the execution was amazing. All the supporting characters had their own thing going and you would end up Loving them just as much as our cute main leads. This drama also had one of the most smoking hot baddie ever (you will end up stalking that guy on Google, for sure) but yeah he was pretty trashy yet interesting character.

ACTING/CAST:-
The acting of almost all the cast members exceeded my expectations.
Park Hyun sik as the super cocky chaebol, Ahn Min hyuk, with the heart of gold had me smittened. He was also so genuinely unabashed about his feelings for bong soon I mean it's just awwwwwww!!!!

Park Bo young was probably the perfect person to play our cutie pie, Bong soon, with hulk-like strength! She was the perfect mix of innocent and badass and you can't help but root for her.

Ji soo as and I quote bong soon "handsome Guk doo" gave an impressive performance and his face offs with minhyuk contributed to some of the major LOLs of the show

Special mention to Won-hae Kim, Jeon Seok-ho and Im Won-hee who played some of the most pivotal roles, without them the show would not have been the same.

MUSIC:-
This is my absolute favourite part of this drama!! All the songs are so well-suited to the premise and I don't think I'll ever get tired of them. The entire ost is currently my most played playlist on Spotify and that ain't changing anytime soon?

REWATCH VALUE:-
You can watch it a million times without getting bored. I find myself going back to the same comic or romantic scenes again and again.

Overall it is one of the best light hearted/mystery dramas out there and trust me you won't regret spending your precious 16 hrs on this particular gem.

HAPPY WATCHING!!