ET Exclusive: George Clooney, Clown Prince

George Clooney is a well-known prankster and all-around clown on the movie sets he works on, and we've got an exclusive look at some of his behind-the-scenes dancing and antics on The Descendants, hitting DVD and Blu-ray Tuesday.

George Clooney: 'I Don't Hate All Children'

"He loves to laugh a lot and tell jokes," says Descendants co-producer George Parra, while Descendants author Kaui Hart Hemmings recalls a moment in which Clooney was rapping with her husband: "They knew every single line to Sir Mix-a-Lot and to all these old rap songs. My husband was very impressed with that. Oh, this George Clooney, he's all right."

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The on-set levity is a welcome distraction from the serious nature of the film's plot, which finds Clooney (nominated for an Oscar for the role) as a caring-but-absentee dad forced to wrangle his kids when his wife falls into a coma. As he weighs a heavy decision involving royal family legacy and inherited land in Hawaii, he discovers that his wife was having an affair behind his back.