The casting rumours always focused on the protagonists Christian Grey and Anastacia Steele. Mia Grey is of the supporting cast that plays an important role in the story of Christian Grey and Anastacia Steele.

One of the characters in the novel is Mia Grey, who is Christian's younger sister. She is described as tall and curvaceous. She also has raven hair that matches her deep dark eyes. She is very close to Christian and is the only woman who can give Christian a hard time and get away with it.

Universal Pictures acquired the rights to bring the successful erotic novel to the big screen. British author E.L. James handpicked the duo who worked on "The Social Network" to be the producers of the movie adaptation of "Fifty Shades of Grey."

The two will perform the very important task of casting actors and actresses who will fill in the shoes of the characters in the mummy porn novel. There is no report yet on who will be part of the cast. However, Ian Somerhalder and Felicity Jones are rumoured to secure the part of Christian Grey and Anastacia Steele, respectively.

"Fifty Shades of Grey" started as a Twilight fan fiction with Isabella Swan and Edward Cullen served as inspirations to the characters of Christian and Ana.

However, the author decided to pull out her work from the fan fiction page and put it up in her own Web site due to the sexual nature of her work and its popularity and wide readership.

The first book was followed by "Fifty Shades Darker" and "Fifty Shades Freed."After publishing her work, the novel now passed the 20 million mark and has a growing fan base. Moreover, a lot of people are interested on who will complete the cast for this controversial project.

Below are some of the actresses who could play the part of Mia Grey in the upcoming film adaptation.