Keeley Hawes will play a major new character in the next series of 'Doctor Who'.
Hawes will play Ms Delphox in series eight of the BBC sci-fi drama.
Hawes can currently be seen in BBC Two's drama 'Line of Duty'.
Delphox is described as a "powerful out of this world character with a dark secret". She will meet Peter Capaldi's Doctor and his companion Clara (played by Jenna Coleman) when they arrive on a strange new planet in episode five of the new series.
"I am delighted to join Doctor Who and to be working with this incredible team," Hawes said. "Ms Delphox is a great character and someone I've had a lot of fun playing."
Stephen Moffat, lead writer and executive producer on 'Doctor Who', said: "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."
Hawes has also appeared in 'Spooks', 'Ashes to Ashes', and 'Upstairs Downstairs'.
Series eight of 'Doctor Who' is currently being filmed, to be broadcast in the autumn. It's the first starring Peter Capaldi as the Doctor.