Academy Award winner Shirley MacLaine will join the cast of Downton Abbey for its third season, which is set to premiere on ITV in the U.K. this fall and will air on PBS's Masterpiece Classic early next year. When shooting on the period drama, created by Julian Fellowes, resumes next month, MacLaine (Terms of Endearment) will join the cast of the multiple Emmy and Golden Globe winner, where she will play a new character, Martha Levinson, the mother of American-born Lady Grantham (Elizabeth McGovern). "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," said executive producer Gareth Neame in an official statement. In the U.S., Downton Abbey's second season, which is up 30 percent in the ratings, is slated to wrap its run on Feb. 19.