George Clooney George Clooney

George Clooney is set to appear in a special one-off charity episode of Downton AbbeyITVannounced Thursday.

Clooney, 53, will star in a sketch as an American guest at a wedding held on the Crawley estate, but further details about his role have not been released.

Watch the first trailer for Downton Abbey Season 5

The sketch will air as part of the ITV charity fundraiser Text Santa, but is not part of the serialized Season 5 episodes or the season's Christmas special.

Clooney and Downton Abbey star Hugh Bonneville co-starred in Monuments Men, which Clooney also co-wrote and directed, earlier this year.

Season 5 of Downton Abbey premieres Sept. 21 in the U.K., and Jan. 4 in the United States.

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