This show is a masterpiece. The plot and characters are so well written. The direction, cinematography, setting, and soundtrack all are spectacular. The acting is the main highlight though. The cast has done such an amazing job. This is Jung Kyung Ho's best work. he has played his character so phenomenally. And the character itself is beautifully written. He's enigmatic, intense, ruthless and surprisingly charming.The drama is dark and moody and deals with various themes like betrayal, revenge, survival etc. It's full of mystery. It's very well-formulated and executed. There are twists after twists. When you finally think you have things figured out it throws another twist at you and you're back to square one. It would take some patience to watch the show but if you're into crime, suspense related shows then you know how these kinds of shows go. It's gritty and violent. If you're looking for comedy or a full-fledged romance then this isn't the show for you. The romance is there but it isn't given as much attention. It's still an important part of the plot though. The best thing about this drama is the focus given on the relationships between characters. The characters are complex with dynamic story arcs of their own. It's a kill or be killed world. It's about surviving in the world of crime. And the ending is poetic justice. You'll know at the end that it's the only way the characters could find peace. Once you're in, you're in for life. This drama is pure art and I cannot recommend it enough.