Fred Madison, a saxophonist, is accused under mysterious circumstances of murdering his wife Renee. On death row, he inexplicably morphs into a young man named Pete Dayton, leading a completely different life. When Pete is released, his and Fred's paths begin to cross in a surreal, suspenseful web of intrigue, orchestrated by a shady gangster boss named Dick Laurent.

In The Equalizer, Denzel Washington plays McCall, a man who believes he has put his mysterious past behind him and dedicated himself to beginning a new, quiet life. But when McCall meets Teri (Chloë Grace Moretz), a young girl under the control of ultra-violent Russian gangsters, he can't stand idly by - he has to help her. Armed with hidden skills that allow him to serve vengeance against anyone who would brutalize the helpless, McCall comes out of his self-imposed retirement and finds his desire for justice reawakened. If someone has a problem, if the odds are stacked against them, if they have nowhere else to turn, McCall will help. He is The Equalizer.

Robert McCall serves an unflinching justice for the exploited and oppressed, but how far will he go when that is someone he loves?