McCall (Denzel Washington) is a retired black ops commando who has been immersed in a life full of violence and danger for many years. McCall's heart has long been exhausted. In order to leave the organization, he went to great lengths to fake the illusion of his own death, came to Boston, changed his face, and hid his identity in an attempt to live a peaceful new life. By chance, McCall met Terry (Chloe Grace Moretz), a young prostitute controlled by the Russian gang. The girl's rough life experience and dangerous situation won McCall's sympathy, and he decided to help the poor girl. However, while rescuing Terry, McCall himself was caught in the powerful firepower of the gang. McCall, who was disappointed with the police's stupidity and corruption, was determined to stand up and fight against the system.