Black Mass. In 1970s South Boston, FBI Agent John Connolly (Joel Edgerton) persuades Irish mobster James “Whitey” Bulger (Johnny Depp) to collaborate with the FBI and eliminate a common enemy: the Italian mob. BLACK MASS tells the true story of this unholy alliance, which spiraled out of control, allowing Whitey to evade law enforcement, consolidate power, and become one of the most ruthless and powerful gangsters in Boston history. The film also stars Benedict Cumberbatch as Whitey’s brother, Billy Bulger, a Massachusetts State Senator; Jesse Plemons as Whitey’s longtime partner in crime, Kevin Weeks; Sienna Miller as Whitey’s lover, Catherine Greig; Dakota Johnson as Lindsey Cyr, Whitey’s former girlfriend and mother of his only child; Rory Cochrane as Steve Flemmi, another member of the Irish mob; Julianne Nicholson as John Connolly’s wife, Marianne; and Adam Scott as FBI Agent Robert Fitzpatrick. Rounding out the main cast are David Harbour, Jeremy Strong, Brad Carter, W. Earl Brown and Corey Stoll.