Felicity Jones has won the role of Ellen Ternan in the movie adaptation of The Invisible Woman .
The Chalet Girl actress will be directed by Ralph Fiennes, who is stepping behind the camera after completing his role as Harry Potter villian Lord Voldemort.
Ellen, or Nelly as she was known to Charles Dickens, was only 18 when she met the 45-year-old A Christmas Carol author.
The story will be based on the novel by Claire Tomalin, which follows the pair on their secret 13-year long affair which lasted until Dickens' death in 1870.
She has beat off stiff competition from actresses Carey Mulligan, Imogen Poots and Abbie Cornish to secure the role as Dickens' mistress.
Filming is expected to kick off early next year but, as Fiennes has already ruled out playing the author himself, the hunt is on for a leading man to play Charles Dickens.
Felicity Jones can next be seen in Like Crazy which opens on 3 February 2012. Ralph Fiennes' directorial debut, Coriolanus , opens on 20 January 2012.