Is nowhere safe from the ever-present threat of the flash mob? Apparently not. Just take a look at this video in which various cast, crew and hangers-on from the set of 'The Big Bang Theory' break into a spontaneous 'Call Me Maybe' song-and-dance routine.

According to The Hollywood Reporter, the clip was filmed during a live recording of the US comedy on 23 October. And it's already had more than 12m hits since it was uploaded to YouTube last Thursday - so people obviously like this kind of thing.

Be warned, though: this video contains prolonged scenes of high-pitched whooping, which some more emotionally contained British viewers may find disturbing.

Well, this all very nice and jolly - but, to our minds, it's still not a patch on the Cookie Monster's 'Call Me Maybe' parody...