Retired Secret Service agent and private investigator Robert McCall (Denzel Washington) is on a killing spree to write the final chapter of his vengeance. Having given up his life as a government assassin, he has struggled to reconcile the horrific deeds of his past, finding a strange solace in serving justice on behalf of the oppressed. In southern Italy, Robert discovers that his new friend is being controlled by a crime lord, and as events turn deadly, Robert knows he must take on the Mafia to keep his friend safe.