Sherlock's Sian Brooke Joins Mission: Impossible 6

03/24/2017 05:59 pm EDT

Sian Brooke has landed a key role in Mission: Impossible VI, according to Variety. Details on her Mission: Impossible role are being kept under wraps, at this time.

The British actress is best known for her role (multiple roles) in the fourth season of BBC's Sherlock. She portrayed Eurus Holmes, the brilliant, master of disguise, mind-controlling, and psychopathic sister of Mycroft and Sherlock Holmes.

What will the film be about? "I've seen five of these movies and I don't know who Ethan Hunt is," director Christopher McQuarrie told Empire. "One movie sort of dealt with his personal life; the other movies are about people speculating what's really going on in Ethan's head. I want to know who Ethan is in this movie, I want an emotional journey for this character, and Tom really embraced it."

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Christopher McQuarrie, who wrote and directed Mission: Impossible — Rogue Nation, is back to write and direct Mission: Impossible VI. It is being produced by Tom Cruise, along with David Ellison and Dana Goldberg at Skydance Productions and J.J. Abrams at Bad Robot.

The cast features the return of Cruise as Ethan Hunt, Rebecca Ferguson as Ilsa Faust, Simon Pegg as Benjamín "Benji" Dunn, and Jeremy Renner as William Brandt. New additions to the cast include Batman v Superman: Dawn of Justice star Henry Cavill, The Crown's Vanessa Kirby, and Sherlock's Sian Brooke.

Mission: Impossible VI is expected in theaters on July 27, 2018.

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