Plot: Yoon Ji Woo, a member of the organized crime ring, goes undercover as a police officer and harbors cold revenge in her heart. Yoon Ji-Woo’s father dies suddenly. She wants to desperately take revenge on whoever is responsible for her father's death. Helping Yoon Ji Woo go undercover is Choi Moo Jin, the boss of, the biggest drug crime group Dongcheonpa in Korea, whose true motives are not easy to read. With the help of Choi Mu-Jin and to uncover the reason for her father's death, Yoon Ji-Woo joins the police department and becomes a mole for the drug group. Jeon Pil Do, a police detective in the Drug Investigation Unit. He becomes Yoon Ji Woo’s partner when she joins the police. Cha Gi Ho, the team leader of the Drug Investigation Unit. He and Choi Moo Jin have long been enemies, with Cha Gi Ho vowing to take down his crime ring before he retires. Do Gang Jae, a former member of the drug ring. After causing problems and getting kicked out of the gang, he vowed revenge against them.

Main: Yoon Ji-woo is seeking revenge for her father's murder.
Jeon Pil-do is a detective.He initially disliked Jiwoo but he ended up falling in love with Ji-woo and ended up getting killed by Mu-jin in front of her.
Choi Mu-jin is the boss of Dongcheon, which is Korea's biggest drug ring. He was best friends with Ji-woo's father.

Review: Liked everything about the drama, i mean everything besides Pildo dying, that was really sad ._. I just want it to be a happy ending for Ji-woo. I think she deserved to be with someone that could love her and be with her in the worst times of her life