Johnny Depp and Amber Heard
Actor Johnny Depp and his fiancee, model Amber Heard, arrive at the Metropolitan Museum of Art Costume Institute Gala Benefit celebrating the opening of "Charles James: Beyond Fashion" in Upper Manhattan, New York, May 5, 2014. REUTERS/Lucas Jackson

An upcoming action crime-drama film, “Black Mass” is based on the 2001 book “Black Mass: The True Story of Unholy Alliance Between the FBI and the Irish Mob” penned by Dick Lehr and Gerard O’Neill.

Directed by Scott Cooper, the all-star cast movie stars “Pirates of the Caribbean” star Johnny Depp, “Fifty Shades of Grey” Dakota Johnson, Joel Edgerton, Sienna Miller and “Sherlock’s” Benedict Cumberbatch.

Playing the lead star Whitey Bulger, Depp is almost unrecognizable as he plays the real life gangster donning a bald cap and wig. Looking like the legendary Jack Nicholson at 77, Depp was photographed wearing prosthetics as he waved to passers-by leaving the Boston set of the film on Wednesday.

Still looking cool in a pair of dark sunglasses, the 50-year-old actor rocked his new character with a gold chain and tracksuit jacket. Best known for his role as Jack Sparrow in Disney’s “Pirates Of The Caribbean” film series, the veteran actor managed to hide his good looks through various eccentric characters like The Mad Hatter in “Alice In Wonderland” and Edward in “Edward Scissorhands.”

The biopic will tell the story of Bulger, a real life gangster who received two life sentences and five years for his part in 11 murders and other crimes including extortion, racketeering and drug trafficking. A big name in the gangster world, Bulger was sentenced last November on his illegal works during the 1970’s to 1990’s.

“The reason to play him is obvious to me,” says Depp in an interview with Collider posted on Daily Mail. “He’s a fascinating character. It’s not like anything I’ve done before, on that level. I’m very excited to slide into that skin for a little bit.”

Very determined to “get to the root of the psychology and behaviour” on his latest film, director Scott Cooper revealed during the interview that he is looking forward to work with Depp. “I only want to work with actors to have a strong point of view and who want to race to set,” he said. “And Johnny is that type of actor. He’s always pushing himself and always playing something different. He’s one of the best actors in American screen history.”

“Our hope is to really craft a full-bodied portrait in ways that you haven’t seen. It’s exciting to see an actor like Johnny really attracted to a part like this because you’ve never seen him like this,” he added.

“Black Mass” will be relased on Oct. 2015.