Background: The story happened in 1935 before the breakout of the War of Resistance against Japan. At that time, in view of inadequate preparation for the war, the national government ordered the armed forces in different places not to attack Japanese initiatively and foment trouble. The place where the story happened is an important river-side town of salt business near to Chongqing. The salt business there is actually controlled by a gang organization named Qing Long Hui, which is both a gang organization and the chamber of commerce for salt industry. Meanwhile, they hate Japanese extremely and serve as a potential anti-Japanese force.
Qing Long Hui has public members and secret members like the chief of police Luo Hongfu. All senior core members should be cut flesh where Guan Gong scraped poison off bones by a gang killer named A Chang (who is also a tattoo master) and tattoo a green dragon on the bones. Therefore, A Chang and gang chief Chi Long possess the information of all secret members.
A Chang has a daughter aged 6 who is mischievous, good at playing slingshot and often fights and makes troubles with neighborhood children. A Chang suspects that Lan Er is the daughter of his wife and Chi Long, which results his wife cannot bear the humiliation and commit suicide shamefully and resentfully. A Chang and Chi Long thereafter bear a grudge. Although their relationship is not broken, they cannot avoid embarrassment when facing with each other. Although A Chang and his daughter rely on each other for living, they are incompatible as water and fire. A Chang feels depressed, indulges in excessive drinking, and likes fighting and prostitution. As an esteemed top killer in the past, he now presents a status as tired of living and without fear of losing life. Therefore, more people try to avoid meeting him except his two brothers the bisexual and Lan Long who still treat him as brothers. Especially the bisexual regards Lan Er as his own daughter.