"La Bola" ("The Ball"), a flash mob inspired by Improv Everywhere and coordinated by Enmedio.
Barcelona, Portal de l'Angel - February 7th, 2009.

The beginning of Improv Everywhere: being Ben Folds. The four main points of Improv Everywhere pranks. The "No Pants" subway ride: from six friends to 1200 people.

One of the first large scale missions: "Look Up More" and the reactions of the three different stores. Another action in a retail store: "Operation Best Buy".

"The MP3 Experiment". 111 shirtless guys in a fashion retail store: "No Shirt".

The "Frozen Grand Central" mission. How the idea spread all over the world (and got coopted too!).

One of the few authorized actions: the Food Court Musical.

The "Human Mirror". The "High Five Escalator". The announcement of "La Bola" action in Barcelona.

Q&A. What are your motivations? Do you do it for profit? About media and announcing missions. What about Improv's  relationship with the press? About breaking the law.

Q&A. What about companies co-opting Improv ideas? Are Improv Everywhere's missions art? Are they pranks? Are they candid camera? Could they be used to promote a social cause? How do you get people collaborating? Ever had any aggression from the people? Is there a "guerrilla theater" scene in New York? Where do ideas for missions come from?