Actress Leaving 'Downton Abbey': PBS Announces Cast for Season 4, Shirley MacLaine Returning, Sarah O'Brien Not

Hit PBS show "Downton Abbey" is in line for some casting changes next season. The show is returning for its fourth season, but not with the same cast. Siobhan Finneran, who played villainous housemaid Sarah O'Brien, is leaving the show. However, there will be plenty of new characters on the show's fourth season.

Tom Cullen will join the cast in season four as Lord Gillingham, an old family friend of the Crawleys who visits the family as a guest for a house party. Nigel Harman will also be added to the cast for season four, playing a valet named Green. Other new actors for next season include Harriet Walter as Lady Shackleton, Joanna David as the Duchess of Yeovil, Julian Ovenden as aristocrat Charles Blake, and Te Kanawa as a house guest

PBS also announced that Shirley MacLaine will return next season as Martha Levinson, the outspoken mother of Cora. Joining MacLaine in season four will be Hugh Bonneville, Michelle Dockery, Elizabeth McGovern, Jim Carter and Brendan Coyle. All returning for for another season.

The third season of "Downton Abbey" just concluded in the United States, with a shocking and tragic end. Spoiler alert for anyone who has yet to finish watching the third season.

Matthew Crawley, one of the show's most popular characters, died at the end of season three after a car crash. Actor Dan Stevens, who starred as Crawley, will be leaving the show. Jessica Brown Findlay, who played Lady Sybil, will also be leaving the show after her character died during childbirth.

"Downton Abbey" airs on the "Masterpiece" anthology and received critical acclaim after winning three Emmy awards last fall. The series has won a total of nine Emmy's, two Golden Globes, and a Screen Actor's Guild Award for best ensemble cast.

The highly popular PBS show is set for another season, despite not having a premiere date just yet. So are you looking forward to another season of "Downton Abbey"?