After the Scavenger case, everyone thought that the murderer was a woman in red, but no one thought that the woman was Han Tianfeng in disguise, and all he did was to target Qin Ming, who he wanted to turn into another Scavenger.
Han Tianfeng brought Qin Ming to the rooftop and handed him the knife that stabbed Prof. Bu to death and told him to kill Li Weihong to become a scavenger, but in the end, Qin Ming didn't do that, instead, Han Tianfeng killed Li Weihong, and after that he turned around and jumped down from the upper floors, luckily, Qin Ming caught him in time, and in the critical moment, Lin Tao arrived in time to save the crowd.
All of this is because of Han Tianfeng's experiences as a child, which gradually made him develop a twisted personality, and even the sense of justice in his mouth is twisted. The story of the scavenger also tells the audience that in this world, no one can be above the law, judging the lives and deaths of other people, and fighting violence with violence.