It was a seemingly normal day on set of The Big Bang Theory while filming last night’s episode (Thursday, November 15)… until Carly Rae Jepsen’s “Call Me Maybe” unexpectedly began to play, and the entire cast and crew broke out into a flash mob!

The dance was a big surprise to both the producers and live audience, who thoroughly enjoyed the performance.

According to Gather, Kaley Cuoco, the actress who plays Penny on the show, is the one who originally had the idea for an amazing flash mob surprise, and organized the whole thing.  It was a big hit!

Check out The Big Bang Theory FLASH MOB below:

What a bummer that Jim Parsons  (who plays Sheldon) did not participate in the dance… we would have loved to see Sheldon let loose for once!!!