Rita joins Dakota Johnson who has been cast as Anastasia Steele and Jamie Dornan, set to play saucy billionaire Christian Grey.
The news was confirmed on Rita Ora's website with the message, "It's official! Rita's been cast in Fifty Shades of Grey as Christian's sister Mia. She will appear alongside Dakota Johnson, Jamie Dornan, Luke Grimes, Eloise Mumford and Jennifer Ehle, with Sam Taylor-Johnson directing.
Fifty Shades of Grey was actually set to launch in August next year, but the launch has been delayed after original leading man Charlie Hunnam dropped out of filming.
Fifty Shades of Grey is due to be released on Valentine's Day 2015, but if you can't wait until then to see Jamie Dornan getting his kit off, check out the first pictures of Jamie Dornan as Christian Grey - we know you want to!
Did you think Rita looks right for the role of Mia? Let us know in the comments section below.
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