At the bottom of the Sabuk area in Gangwon Province, the wild dog-like Heo Yingda (Kim Jae-joong) and his friends are eating, drinking, gambling, fighting, cheating, and doing all kinds of evil. He and the rich young man Yin Yangxia (Lim Siwan) who is playing against him at the gambling table are like two people from two different worlds. The appearance of the beautiful girl Wu Jingxi (Baek Jin-hee) further escalates the confrontation between the nobleman and the little ruffian. At the same time, Yingda, who is licking blood on the knife, is inevitably involved in a murder case. During this period, he encountered the tough detective Zhang Dongxiu (Lee Beom-soo) of the Seoul Metropolitan Police Agency's Wide Area Search Team. Yingda and Dongxiu, who are in the black and white worlds, and Yangxia, who spends money like water, gradually know the incredible origins and connections between each other while colliding fiercely. The miserable fate of childhood has given the three men a tortuous life.