Black Mass is a crime drama film in which Benedict Cumberbatch plays the role of Billy Bulger, a prominent politician and brother of notorious gangster Whitey Bulger. The movie tells the true story of Whitey Bulger's criminal empire and the FBI's attempts to bring him down. Cumberbatch's performance as Billy Bulger showcases his versatility as an actor, portraying a character torn between loyalty to his brother and his political ambitions. Black Mass is a gripping and intense film that delves into the dark underbelly of organized crime.