First of all, watch this without any expectations.

I find this drama super enjoyable and fun to watch. Although there are parts of it that I'm not fond of but overall the story is engaging and make me want to keep on watching.
I know there's a lot of negativity towards the drama or the actors, but for me, the casts were perfect fit for their roles and the story was interesting enough for me to keep watching it despite my busy schedule (I really watched super late some days).

Ok first of all, Rowoon's acting really improved a lot, I probably love his acting here in this drama and will be my favourite. As he act as "Jang Sin Yu", I sometimes almost mistake it as his own character in real life (that's how impressive his acting to me is). He sure is not only just handsome and tall but his acting is on point. Hope he will keep improving as his acting career soars.

Well.. there's a lot of hate towards Jo Bo Ah acting. However, I don't really agree to it. For me, her acting is always good and on point. I've watched several of her dramas and movies and she did deliver and portrayed her characters very well. I will always root for her in dramas. Her acting as "Lee Hong Jo" was a great one (compare to her last drama where she played a tough character).

Of course, the one acting as villains were as good as the main one to the point I started to hate them every time they showed up on screen (LOL).
All the side characters were great as well. They were cute, funny, sometimes annoying but always fun to see them on screen.
Therefore, I think the producer and writer did really well casting all the actors & actresses befitting all the characters they portrayed. Good Job!!!

Story line, well how to I put it, its easy to follow not as complicated as it sounds. For me the story was very engaging and kept me on edge towards new eps.

In the end, it's back to your own preferences. As for me, I always try to watch several episodes before deciding whether to continue or not without being biased towards the comments. (There were some dramas that disappoint me that I either dropped it or hate it after finish watching it).

Oh one more thing, that all the of CGI they used here are very cool (especially the bloody hand that sometimes appears, it did gave me the creeps).

I do hope you will enjoy this drama as much as I do. Try watching a couple of eps and decide then.
Hope this review will help you . ^^