Rita Ora Joins 'Fifty Shades of Grey' Movie; Singer Cast As Christian Grey's Sister Mia

Rita Ora is the latest star to join the film adaptation of the best-selling erotic novel!

Rita Ora is the latest star to join the film adaptation of the best-selling erotic novel!

Splash

Oh brother... Christian Grey just got a sister!

As The Hollywood Reporter first reported, singer Rita Ora is the latest star to join the much-anticipated, big screen adaptation of the best selling erotic novel! The 23-year-old songstress will be taking on the role of Mia, the younger sister of Christian—played by Jamie Dornan.

Rita confirmed the news on her Twitter, writing, "It's official! I've been cast in Fifty Shades of Grey as Christian's sister Mia!"

PHOTOS: Fifty Shades of Grey Begins Filming!

The British beauty is best known for her musical career—she is signed to Jay Z's Roc Nation label and had three consecutive No. 1 singles—but she has ventured in acting previously, with a cameo in Fast & Furious 6 and a role in the British film Spivs.

Since it was revealed that the very popular book was being adapted for the big screen, casting has been no small task for the production; when the original leads were announced—Charlie Hunnam and Dakota Johnson—online petitions called for them to be recast; Charlie, who stars in Sons of Anarchy eventually dropped the project.

E.L. James Releases ‘Fifty Shades’-Themed Wine!

Author E.L. James told Entertainment Weekly that she was "terrified" of making the movie because of the dedicated fan base.

"I've been terrified from the moment I published the book." She admitted, when asked how she was feeling about the upcoming production. "You don't expect this kind of success. Even now it floors me. My only ambition for the books was to see them in bookstores. This is huge. And there is this passionate fandom; we need to get this right for them."

PHOTOS: Meet Jamie Dornan, Your New Christian Grey!

Ms. James has been hands-on with the entire production—she was even in Vancouver this past weekend when cameras started rolling!

The film is slated to hit theaters Valentines Day weekend 2015.

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