The 1950s saw a surge in unemployment and crime in the capital, Tokyo. In order to suppress the anti-government forces, the government established a force directly under the National Public Security Commission - the Capital Police. Fu, who abandoned his emotions and only had his fighting instinct, was one of them. One day, Fu was ordered to track the left-wing elements, but found that the other party was just an underage girl who was responsible for delivering bombs. After a little hesitation, the girl blew herself up and died. Because of this incident, Fu was sent back to the training school. A few days later, Fu went to the girl's tomb, where he met the girl's sister, Amamiya Ke. Through contact, the two gradually developed feelings. However, Kyu is not the girl's sister. She was also a member of a left-wing organization and was hired by Bian Jian of the Ministry of Public Security as bait. Bian Jian uses the relationship between Kyu and Fu to create a scandal, and wants to force the capital police to disband. And Bian Jian's plan was already noticed by the capital police cadre Handa, and Fu also just pretended to be deceived. Fu will kill the leaders of the anti-capital police forces one by one, but facing Gui, he is difficult to start.
In the decades after World War II, Japan gradually emerged from the shadow of defeat and entered an era of high economic growth. However, the tough economic policies have also led to the rising unemployment rate, various anti-government armed forces have continued to rise, and the stable social order has disappeared. In order to deal with this problem, the government has established a high degree of autonomy in the metropolitan area security police agency, and has used sophisticated equipment and decisive force to combat anti-government organizations headed by "parties". With the continuous development of the economy, the police and "parties" in the metropolitan area, which advocate violence, have gradually been rejected and isolated from the public.
In a fierce and bloody battle, A Chuan, a girl belonging to a "partisan", detonated a bomb and committed suicide. Fu Yigui, a member of the Metropolitan Police who witnessed this scene, suffered an unprecedented shock. From this moment on, his life has quietly changed.