American flavour as Shirley heads to Downton

Maggie Smith’s character, the dowager countess, is one of Downton Abbey’s most loved, but her witty asides and lines like “what’s a weekend?” will soon be put to the test when Shirley MacLaine heads to town as Lady Grantham’s American mother.

The Oscar-winning actress and star of more than 60 films, including In Her Shoes, The Apartment and, most famously, Terms of Endearment will play Martha Levinson, the mother of Cora Grantham.

In the first two series of Downton Abbey, heiress Cora Grantham is the only American character and married Lord Grantham because of Maggie Smiher substantial fortune. The couple have three daughters, and their search for a male heir makes up a large part of the narrative.

Executive producer of the ITV drama series, which airs on PBS in the United States and Channel 7 in Australia, Gareth Neame said in a statement: "My late grandfather directed Shirley MacLaine in Gambit in 1966 so it is a delight for me that she will be joining us on Downton Abbey.

"Julian Fellowes has written another brilliant character in Martha Levinson, who will be a wonderful combatant for the dowager countess and we are excited at the prospect of Shirley MacLaine playing her."

The third series will begin filming this month and will take place in the years 1920 and 1921. The show won a Golden Globe last month for best television mini-series as well as four Emmy awards in 2011 - a rare achievement for a British show.

Downton Abbey is an “upstairs, downstairs” drama that details the lives of the servants and Lords and Ladies of a grand English house just after the turn of the century. It focuses on the class system and World War One.

The show’s Christmas special attracted an average of 8.1m viewers between 9pm and 11pm in the United Kingdom and has also drawn huge ratings for its American broadcaster, PBS.

Laura Mackie, director of drama at ITV, said in a statement: "It is so exciting to have an actress of Shirley MacLaine's stature joining our brilliant Downton Abbey cast for series three and a tribute to the show's success on both sides of the Atlantic."