Published Thursday, 29 May 2014
Sue Johnston previously played Gloria Price on Coronation Street. (© Getty)
The actress, best known as mum Barbara on The Royle Family, will play the guest role of Denker who is lady's maid to Dame Maggie Smith's Violet, Dowager Countess of Grantham.
She is the latest famous name to sign up for a guest role in the show, joining stars including Richard E.Grant and Anna Chancellor.
The show returns to UTV this autumn and again at Christmas for a feature-length episode.
Its creator Julian Fellowes has previously hinted that the next series of the hit show could be its last.
The period drama, telling the story of the aristocratic Crawley family, made its debut in 2010, but Lord Fellowes, who is also an actor, said: "I don't know yet if there is a season six, but it's not going to go on forever."
© UTV News