I tend to avoid crime-based shows that mix in romantic subplots and comedy because it either becomes TOO romantically based or it's TOO reliant on the comedic factor and the serious tone is lost in the process. However this drama was everything that I never knew I needed. Some might complain about the lack of romance but I don't think that was ever supposed to be the point. It was just a bonus. I stepped in not knowing a lot about the plot, deciding to watch it on whim since I'm a big fan of Seo In Guk and Jang Na-Ra but I got so much more out of it then I was expecting. The concept was well thought out and made their viewers think throughout the entire series; are monsters born or are they created? If you are marked out for a certain path, do you just have to accept or is there a secret back door waiting somewhere? Do children inherit their parent's sins and SHOULD they? As a viewer, you are proposed these type of questions (and many more). Yes, there are some funny moments and the romance is sweet but the psychological aspect is what truly made it stand out from the rest of the crime-based shows that year. The cast had great chemistry and there wasn't a single member that I felt came short or could of been replaced. Everyone was important. Choi Won-Young and Park Bo-Gum played their roles in an effortless like manner. The characters were complex, well writing and left me wanting more of them. The female lead wasn't just 'strong' for the sake of pleasing the audience. Nor was she flawless either. She was perfectly 'imperfect' She was indeed strong but she also got hurt, she cried and she also grew a lot throughout the series. Her character was just as interesting as her fellow cast-mates which isn't entirely common when you have such a male-based lineup. Overall I would definitely recommend that you check it out. From the story-line to the OST, I don't think you'll be disappointed.