Tan Songyao (Michael Miu) and Tan Songshun (Eason Chan) are the sons of triad boss Tan Xintian (Wang Zhiwen). The two brothers were separated by their father when they were young. When Yao grew up, he took over his father's gang and was determined to reform, wanting to get on the right track. However, Uncle Jiu and his son Yan Guoqu (Tang Zhenye) in the gang did not want to give up their illegal activities and were eyeing the position of gang boss. On the other hand, Detective Kui (Andy Lau) closely followed the actions of the Tan family gang and collected evidence of crimes. Tan Xintian was killed and Tan Songshun returned to Hong Kong. He accidentally killed Uncle Jiu while driving and fled to Thailand accompanied by Shun's girlfriend Zhuang Qing (Huang Yi), but he was repeatedly in danger. Fortunately, he was rescued by his trusted A Gui (Felix Wong) and survived. What happened one after another made Tan Songshun doubtful, and the trust between the two brothers was put to the test. At the same time, the hexagram of the "Xuanwu Gate Incident" in his childhood seemed to be slowly coming true...