Wikipedia defines a flash mob as “a large group of people who assemble suddenly in a public place, perform an unusual and pointless act for a brief time, then quickly disperse”. Flash mobs tend to be produced by two very different groups, corporations or companies trying to advertise a campaign or product, or everyday people for fun or trying to send a message in a very public way. One again flash mobs have two distinct audiences; the people there to witness the event to take place, who film it and then post it online, leading to the second group, which is the people who hear of these online videos and watch online. The main characteristics of this genre are an intro of some kind helping to place the event, a very public place found either indoors or outdoors, a gradual growth in group size throughout the event, reaction shots of the crowd found at the event, and an anticlimactic ending.
Most every official flash mob video, official meaning the group responsible had multiple camera people there to film the event from different angles and then edit together to create a larger view of the event, begins with an intro of sorts that helps place the setting or the purpose or the event. For example, the Bristol Light Saber flash mob they spoof the beginning of the actual Star Wars beginning, with a faux 20th Century Fox logo, instead named Bristol LIghtsaber Flashmob, and a faux Lucas films logo, instead named Clatterowls Inc. They then proceed to spoof the original text found at the beginning of the film, instead saying “Not so long ago, in a mall in Bristol”. (http://www.youtube.com/watch?v=rUZgrL85OKs) Other videos will just help you get a feel for the setting by showing multiple shots of the location just so the viewer has an idea of the space.
Almost all flash mobs take place in a very public place of some kind, from a Student Union at a large University to a famous monument. Their was a flash mob at the Ohio State University Student Union (http://www.youtube.com/watch?v=UJux_VTITfI), at the Sydney Opera House (http://www.youtube.com/watch?v=qpgr3vDK5Bc), even the famous Bondi beach has been home to multiple flash mobs. Another quality that the majority of flash mobs share is that, no matter what kind of flash mob be it a dance or a sword battle, the full group participating does not usually all begin at once. The event begins with a few of the members starting of the confusion, with more and more people joining as the time passes by causing even more uncertainty in the audience. A great example is one of the mobs that occurred at Bondi beach (http://www.youtube.com/watch?v=Ao4DkbGbxl0); it began with a drag queen hearing the loud music and she alone started to dance, only shortly after for four or five participants to pop up behind her and join in the dance.
A very important part of flash mob videos is reaction shots of the live audience to the actual mob. These reactions show the real spontaneity of the event, almost used to prove that this really was an unexpected event and a complete surprise to everyone there. They also like to show shots of these audience members taking out their phones and capturing videos of the event so they can prove they were there when it happened. A great video showing the reaction of the “audience” was the freeze flash mob in Grand Central Station in NYC (http://www.youtube.com/watch?v=jwMj3PJDxuo). The goal was to freeze simultaneously for four minutes and then just unfreeze and continue on. The video goes so far to show a cart driver calling his superiors saying he needs help because there are all these bizarre people frozen that are blocking his way, only for the group to start moving and him to radio “never mind”.
Lastly a fair amount of flash mobs come to an almost anticlimactic end, with the group typically suddenly stopping and then fitting themselves back into the crowd of ordinary people like they never did anything. A T-mobile ad campaign created a flash mob in the Liverpool Street Station (http://www.youtube.com/watch?v=VQ3d3KigPQM), where all of the previous characteristics were portrayed, when the last song clip suddenly ended with all the dancers with the hands in the air, suddenly everyone dropping and picked up their belongings and went back to walking through the station to the places they needed to reach. This helps accomplish that feeling of a fleeting event that is unexpected and like a flash of lightening there and then gone.