The former ER actress will play Dr Blanche Mottershead, “a free-thinking and outspoken archaeologist who smokes cheroots and who is fond of a ‘little light nudism’”, reports The Daily Mail.

She commented: “Alex Kingston says: “I simply couldn’t resist the opportunity to get inside the iconic 165 Eaton Place and join a show steeped in such history but that has been revived for a whole new generation. I will be playing the uncompromising, straight speaking spinster, Dr Blanche Mottershead, the younger sister of the late Maud, Lady Holland and Sir Hallam’s Aunt. Heidi [Thomas, writer] really has created a wonderfully, intriguing character in Blanche who will, over time, reveal some secrets of her own.”

Originally airing on ITV from 1971 to 1975, Upstairs Downstairs was revived in 2010 for three episodes which aired on BBC One last Christmas. Starring Keeley Hawes (Ashes to Ashes, Spooks), six new 60-minute episodes of the show will air early next year, set in 1938.

Kingston returns to BBC One next weekend as River Song in Doctor Who‘s Series 6 finale. Written by showrunner Steven Moffat, ‘The Wedding of River Song’ will air at 7.05pm on Saturday 1st October.

> Order the Series 6 DVD boxset on Amazon.

> Order the Series 6 Blu-ray boxset on Amazon.

Watch the trailer for the episode…