In the seventh episode of the second season, six suspects robbed Building 202, wuyi avenue Avenue, Changsha City with machetes, wires and other tools, and snatched two mobile phones and cash 500 yuan from a victim. After receiving the police, Changsha Kaifu Criminal Investigation Brigade and Tongtai Street Police Station jointly launched an investigation and found an evil gang that had been entrenched in Wuyi Square, Xichang Street and Jiefang West Road in Changsha for a long time, gathering people to fight, make trouble and rob. They call themselves "Justice", "Liberation of West Mobile" and "United Nations Liberation of West Anti-Black Brigade". After receiving the police, Kaifu Criminal Investigation Brigade and Tongtai Street Police Station jointly launched a case investigation. Police investigations revealed that the six men were employed by others and attempted to rob the house. The six suspects came from an evil gang that had been entrenched in Wuyi Square, Xichang Street and Jiefang West Road for a long time.

With the in-depth investigation of the case, the police found that the gang had been gathering people to fight for a long time and participated in underground police activities such as "standing on the wall" with a knife. Changsha Kaifu police quickly dispatched elite police force and set up "4. 10" task force to carry out special investigation.