Hawes will play Ms Delphox, a powerful out-of-this-world character with a dark secret. Travelling across space and time, the Twelfth Doctor (Peter Capaldi) and his companion, Clara Oswald (Jenna Coleman), will come face to face with the mysterious Ms Delphox, when they arrive on a strange and puzzling planet.
The character will appear in the fifth episode of the series, written by Steve Thompson and directed by Douglas Mackinnon, which is currently being filmed in south Wales.
Hawes is best known for roles in The Last September, an adaptation of Elizabeth Bowen's 1929 novel, as well as playing Zoe Reynolds in Spooks, Alex Drake in Ashes to Ashes and Lady Agnes in Upstairs, Downstairs. She is currently playing Detective Inspector Lindsay Denton on the second series of the BBC Two drama Line of Duty. She was the voice of Lara Croft in several Tomb Raider video games.
Commenting on her role, Hawes said:
I am delighted to join Doctor Who and to be working with this incredible team. Ms Delphox is a great character and someone I've had a lot of fun playing.Lead writer and executive producer Steven Moffat added:
Anyone watching Jed Mercurio's amazing Line of Duty will know that Keeley Hawes is having one hell of a year. And now it's about to get even better as she achieves the greatest villainy yet attempted on Doctor Who: she plays a banker.