Crimes do not distinguish between adults and children, they are all bad people. Single father Li Changfeng (Wang Qianyuan) embarks on the road of revenge in despair after his daughter was abused and died by several minors. He seems to want to use his own methods to make the young demons pay the price they deserve. Faced with the pursuit of Li Changfeng and the police, what kind of punishment will these young offenders receive? The film is based on Keigo Higashino's novel of the same name.