Science fiction fandom other groups including LGBT communities, libertarians, neo-pagans, and space activist groups like the L5 Society, among many others. Some groups exist almost entirely within fandom but are distinct and cohesive subcultures in their own rights, such as filkers, costumers, and convention runners (sometimes called "SMOFs"). Fandom encompasses subsets of fans that are principally interested in a single writer or subgenre, such as Tolkien fandom, and ("Trekkies"). Even short-lived television series may have dedicated followings, such as the fans of Joss Whedon's "Firefly" television series and movie "Serenity", known as Browncoats. Participation in science fiction fandom often overlaps with other similar
Agents of S.H.I.E.L.D. series called "S.H.I.E.L.D." to be written and directed by Joss Whedon, with Jed Whedon and Maurissa Tancharoen also writing. Disney CEO Bob Iger greenlit the series after watching the Marvel One-Shot short film "Item 47". In April 2013, ABC announced that the series would be titled "Marvel's Agents of S.H.I.E.L.D.", and it was officially picked up for a full season of 22 episodes in May 2013. Jed Whedon, Tancharoen, and Jeffrey Bell act as the series' showrunners, with Bell joining the show to help the inexperienced former pair with hiring crew members and "navigating the politics of studios and networks",