You’ve heard of a flash mob before, but what about ‘flash musical’? The good fun folks at ImprovEverywhere bring us this holiday singing fun for the whole family. In a mall in New Jersey, the classic Santa scene is set up in the courtyard. Out of the blue, a man starts singing about Santa Claus. Curious and confused shoppers watch in awe as more and more people jump into song and dance. Finally, even Santa adds to the singing to end the musical with a bang.