LONDON, Sept. 18 (UPI) -- George Clooney made quite an impression on the set of Downton Abbey.
The 53-year-old actor filmed a special short with the series to benefit network ITV's Text Santa fundraiser. Clooney will portray an American guest who attends a wedding at Downton Abbey, and reportedly will appear alongside Violet (Maggie Smith), Robert (Hugh Bonneville) and Mary Crawley (Michelle Dockery).
"It's amazing and we didn't even know if it would actually happen until he turned up," star Laura Carmichael, who portrays Edith, told ITV. "We were filming away and then heard, 'He's here, he's here, he's arrived.' But he was wonderful and so brilliant and I'm very excited for everyone to see it."
"There is a very brilliant moment with Maggie and George -- and I don't know if I want to give away any more than that, really -- but Maggie does a very comedy fall -- George plants a kiss and Maggie ends up on the floor, it's wonderful," she revealed. "He was hilarious."
The charity sketch will air Christmas Day on ITV. Downton Abbey airs on PBS in the U.S., and will return for a fifth season January 4, 2015.