As someone who almost always prefers shorter dramas/shows in general, I can't believe im saying how much I WISH this were longer.
The premise is pretty basic, your classic revenge story where the main characters vows to avenge a loved one's death, you can never go wrong with this! The begining of the drama was exceptionally good, introducing a set of intriguing characters and bad-ass action and fighting sequences( these stayed consistently great throughout the show) that only got me more excited for what was coming next. The middle and ending never quite outdid the begining, they didn't even do as much to reach it but my main problem lies elsewhere.
Even though this was an easy and enjoyable watch, I think both the story and the characters had so much potential to elevate this even more had they had a bit more time to develop. The relationship between the main leads was rushed and came out of nowhere, meanwhile we only got to see each character's one side and get a full grasp of who they really are ( except maybe for jiwoo). This problem to me is most obvious when looking at the character of gangjae: we were already familiar with and what he can do from the very begining, he had solid motivations for his actions and he was -to me- a great villain with a seemingly good plan to take revenge from mujin and jiwoo. But he was so underutilised and only was a threat for 3 episodes? The show had to get rid of him so fast because they didn't have more time.
Had this been 10 or 12 episodes long, I believe would have given all characters more depth and thus each big plotwist, a character's death and every other important event would have bigger impact.