Paul Giamatti is heading to Downton Abbey. The actor will join the hit Masterpiece Theater/PBS show in its season four finale, which will air sometime next year.
The Sideways actor will portray Harold Levinson, the "maverick playboy brother" of Cora Grantham (played by Elizabeth McGovern), TVLine reports. He'll appear in the episode alongside Shirley MacLaine, who will return as their mother, Martha.
According to executive producer Gareth Neame, the character of Harold is "free-spirited" and he and Martha will "upset the Grantham's apple cart" in the finale.
The fourth season of Downton Abbey debuts on January 5th, 2014 on PBS.