Cuoco, 31, was put on the spot when an audience member asked if she knew the lyrics, and Fallon urged her to perform them. “I can try,” she said, proceeding to tackle the dense tune with zest.
A quick history lesson: The Big Bang Theory creators Chuck Lorre and Bill Prady asked Ed Robertson of Barenaked Ladies to come up with a song that would serve as a “sort of history of everything … in about 32 seconds.” The result was this catchy — but wordy — theme.
Cuoco and the rest of the cast will now have plenty more opportunities to sing it, as CBS renewed The Big Bang Theory for another two seasons.
The Big Bang Theory airs Thursdays (8 p.m. ET) on CBS.