It's a bit difficult to write an in-depth review without spoilers (and this drama is best enjoyed going in blind) but Flower of Evil is hands-down one of the best kdramas I've seen to date. It's gripping, the plot is well-done (barring a few plot holes), the character development is incredible, and the ending, which some viewers disliked, I found fitting. Plot aside, Moon Chaewon and Lee Joongi were incredible and had amazing chemistry. I can confidently say this is Lee Joongi's best performance so far, and his nuanced expressions really brought his character to life.

I think it's important to note that those who really adore Flower of Evil are the ones who are fall in love with the characters rather than the overall crime plot. While majority of the show is crime/thriller, the core of it is the main characters and their relationship. If you have no interest in seeing their relationship unfold, the main themes and emotional impact of the show will simply fall flat. I suggest go in as blind as possible, watch at least three episodes, and hopefully it will enrapture you as much as it did me.