Alex Kingston to join Upstairs Downstairs cast

Kingston has recently been seen in the BBC's Doctor Who

Actress Alex Kingston is to join the cast of Upstairs Downstairs when the BBC costume drama returns next year.

The former ER star, recently seen in the BBC's Doctor Who, will play Blanche Mottershead, the younger sister of Dame Eileen Atkins' character Lady Holland.

"I simply couldn't resist the opportunity to get inside the iconic 165 Eaton Place," said Kingston, 48.

Her casting follows Dame Eileen's announcement that she would not be returning for the next series.

The 77-year-old conceived the idea for the original 1970s series with fellow actress Jean Marsh but did not appear in it prior to its revival last year.

The new series, which begins shooting in October, will begin in 1938 and span the months leading up to the outbreak of World War II.

"Outside 165 Eaton Place, London and Europe are poised on the knife-edge of calamity," said writer Heidi Thomas.

"Inside, there's a whole world of dark and dangerous emotions to explore."

"Heidi really has created a wonderfully, intriguing character in Blanche who will over time reveal some secrets of her own," said Kingston.

Actor Kenneth Cranham will also join the cast of the BBC One drama, which follows the fortunes of the masters and servants who cohabit a London townhouse.