who developed the above crossover event we talked about?
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when does the flash show up in arrow December 2, 2014 is this a film? It is an Arrowverse crossover event what do you mean by this first term you used in your answer? The Arrowverse is an American media franchise and a shared universe that is centered on various interconnected television series when was it launched? October 2012 can you name any two of such tv series? "The Flash", "Legends of Tomorrow", "Supergirl" does it also support audio series? Audio studio Serial Box is currently developing an audio series for it
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Flash vs. Arrow [SEP] Development
The first indication of potential crossover events in the Arrowverse occurred on The CW during the 2013–14 television season, when Barry Allen was introduced in the eighth episode of "Arrow"s second season ahead of the debut of "The Flash". In July 2014, it was announced that the eighth episodes of the third season of "Arrow" and the first season of "The Flash" would be a two-hour crossover event. The crossover was originally planned as the seventh episodes of each series, but was pushed back due to the large amount of work needed to accomplish it. In particular, the schedule coordination of trying to "jam another episode into the 23-episode schedule for each of [the] shows." Marc Guggenheim, creator and executive producer on "Arrow", explained that there was "no financially responsible" way of executing the crossover, with budgets being blown, long hours and the actors having to film scenes from both series on the same day.