The event in question was an aspirant “flash mob,” in which an “inexplicable crowd”—as described by the originator of the first mob, a New Yorker known simply as “Bill”—is summoned to a particular ...

One very popular example of a flash mob is the March 2009 video that featured over 200 participants in Antwerp, Belgium, Central train station who spontaneously broke into choreographed dance steps to ...