Sienna Miller's Role Cut From Johnny Depp's Black Mass Movie: Find Out Why!

Sienna Miller's role was cut from Johnny Depp's upcoming movie Black Mass Credit: Amy Graves/WireImage

So long, Sienna! Scenes that Sienna Miller filmed for the upcoming Johnny Depp movie, Black Mass, have been left on the cutting room floor, according to The Boston Globe.

The British actress, 33, played Catherine Greig, a girlfriend of real life gangster Whitey Bulger (Depp). Greig accompanied Bulger when police arrested him in Santa Monica, Calif., back in 2011. Greig pleaded guilty for harboring a fugitive and was sentenced to eight years in prison.

Bulger, meanwhile, was found guilty of 31 counts — including extortion, money laundering, and 19 counts of murder — in August 2013. He was sentenced to life and remains at the United States Penitentiary Coleman II in Sumterville, Fla.

Last November, Miller opened up about working on the film. The newly single mom — who shares daughter Marlowe with ex Tom Sturridge — even worked with a dialect coach to make her Boston accent believable.

"Up until the day before I flew here, I couldn’t do it and it sounded stupid," she told the Globe at the time. "And I was sort of religiously watching every film ever set in South Boston: Good Will Hunting, Gone Baby Gone, The Town. Catherine had a thick accent, so I hope I do it justice."

Indeed, she did. But unfortunately, producers went in another direction. "[She was] fantastic," director Scott Cooper said. "It came down to narrative choices."

The crime drama is packed with a star-studded cast. Actors that were lucky enough to make the cut include Benedict Cumberbatch, Dakota Johnson, Joel Edgerton, Juno Temple, Corey Stoll, Kevin Bacon, Adam Scott, Peter Sarsgaard, and Jesse Plemons.

Black Mass hits theaters on Friday, Sept. 18.

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