Paul Giamatti

Emmy winner Paul Giamatti is joining the cast of Downton Abbey, TVLine reports.

Giamatti will play Harold Levinson, the free-spirited playboy brother of Cora (Elizabeth McGovern) and uncle to Mary (Michelle Dockery) and Edith (Laura Carmichael). He'll be introduced in the Season 4 finale.

How Downton Abbey broke our hearts

Giamatti's past TV credits include the titular role in HBO's miniseries John Adams, which earned him an Emmy and a Golden Globe.

Downtown Abbey Season 4 premieres in the United States on Jan. 5 on PBS.