The Black Mass trailer focuses on the life of infamous gangster James "Whitey" Bulger set primarily in the 1970s in Boston. It shows a tense dinner scene between Bulger and his gang members and switches to other locations like a nightclub and FBI office as Bulger narrates in a dark monologue. The trailer uses dark lighting and costumes to portray the dark world Bulger inhabits and quick edits to showcase many clips in typical trailer fashion. It highlights Johnny Depp's extensive makeup used to resemble the real Bulger in this true crime drama.