Watch: Johnny Depp is a horrible father in new 'Black Mass' trailer

Maane Khatchatourian

When Johnny Depp's real-life character Whitey Bulger isn't shooting his enemies point-blank or choking them with rope, he's doling out advice to his 6-year-old son.

Warner Bros.' first official trailer for the upcoming drama "Black Mass" offers this pearl of wisdom from Depp: "It's not what you do, it's when and where you do it, and who you do it to or with," the most wanted gangster in U.S. history says at the dinner table.

"If nobody sees it, it didn't happen," he continues to the disappointment of his girlfriend ("Fifty Shades of Grey" star Dakota Johnson).

The biopic about Boston gangster James "Whitey" Bulger, who became an FBI informant and used this status as a way to eliminate criminal competition, spans the 1970s, '80s, and early '90s.

"Black Mass," directed by Scott Cooper, also stars Benedict Cumberbatch, Kevin Bacon, Joel Edgerton and Peter Sarsgaard. It hits theaters on September 18.

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