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Fans of The Big Bang Theory might logically assume that the cast of the hit CBS comedy has as many laughs on-screen as off. But now there is concrete proof as Kaley Cuoco just revealed in this clip of cast and crew members surprising showrunners with a flash mob of Carly Rae Jepsen's viral hit Call Me Maybe!

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Kaley explains on The Big Bang Theory's Facebook page that the idea was hers and that she recruited her sister Bri to choreograph the impromptu number, which occurred during a taping on October 23 in front of a live audience.

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The clip shows how the prank was carried out with secrecy and precision, with the cast re-assembling on the set immediately after the flash mob to resume taping and to hear star Jim Parsons sum up the event with one of his character Sheldon Cooper's favorite words, "Bazinga!"

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