Lords and ladies, you might want to sit down for this.

George Clooney is coming to "Downton Abbey" for a special charity film this Christmas. A spokesperson for "Downton Abbey" confirmed the news to HuffPost Entertainment:

"George Clooney will appear in a short Downton related charity scene for Text Santa which is a fund raising campaign initiated by ITV the UK Broadcaster of Downton Abbey. The campaign supports six different UK based charities every year and the film will air in December as part of TEXT SANTA."

Clooney has reportedly already shot his scenes and will play an American attending a wedding at a country estate. Though details are being kept under wraps, multiple sources report Clooney may appear alongside "Downton" star, and his "Monuments Men" co-star, Hugh Bonneville.

According to The Sun, an insider source said, “This is the biggest moment in 'Downton' history and shows it’s now the biggest drama in the world.”