Prankster George Clooney was up to his old tricks on the set of "Up in the Air" -- and co-star Anna Kendrick got back at the sexy actor by pitting him against her fellow "Twilight" star Robert Pattinson!

george clooney anna kendrick robert pattinson

"George gave me such a hard time about shooting 'Twilight,'" Kendrick, 24, reveals on Friday's episode of the Ellen DeGeneres show. "Whenever I came back, it was like, 'Oh sorry, this isn't the Twilight set. You're not working with Mr. Handsome.' He called Rob 'Mr. Handsome.' "

See photos of Rob and the other stars on the "New Moon" set

Anna admits she helped fuel the playful competition, asking Robert to sign a GQ magazine with, "To George, Best of Luck. Hang in there. Love Rob."

See how George Clooney has changed over the years

George retaliated against the vampire, sending him an Esquire magazine signed, "Dear Rob, Thanks for all the inspiration. I'm a huge fan. Love, George, two-time 'Sexiest Man Alive.' "

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