In order to restore the image of the police in the eyes of the public and make great achievements for individuals, the newly appointed Sanpu City Police Director Li Chengyu (Sun Binghao) decided to carry out a bank mock robbery drill, of course, the attitude towards this training is tacit, and everyone knows that this is just a show, but the patrol policeman Zheng Duman (Zheng Zaiyong), who is arranged to play the robber, does not think so. Zheng Duman, who is usually unknown and meticulous, went all out to study the modus operandi of the robbers and completely entered the role. On the day of the exercise, Zheng Duman's professional performance shocked everyone. Police plainclothes and commandos were "killed" one after another under Zheng Duman's gun. Li Chengyu, who had planned to be in the limelight in front of the media, failed, but there was nothing he could do about Zheng du. How on earth should this "robber" exercise end? The screenplay of this film is written by the famous Korean screenwriter Zhang Zhen, whose well-known works include "Welcome to Dongmo Village" and so on.