George Clooney will star in Downton Abbey.
The Hollywood A-lister is to make a one-off appearance alongside the cast of the ITV drama as part of this year's Text Santa charity appeal.
George Clooney / Credit: WireImageSpeaking to The Sun newspaper, a source said: "This is the biggest moment in 'Downton' history and shows it's now the biggest drama in the world.
"All the plans have been shrouded in secrecy because George was determined for his role not to leak out."
Having already filmed his scenes for the TV special, he's reportedly attending a wedding at the Yorkshire estate as an American in an episode airing on the same night as the annual event.
The role came about after George struck up a friendship with Hugh Bonneville, known to Downton fans as Robert Crawley, after they both starred in The Monuments Men earlier this year.
The source continued: "George and Hugh became really close during filming and it became very clear that George loved 'Downton.' He would joke around about the idea of getting a part so Hugh helped put the wheels in motion to make it happen."
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