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
U.S. television science fiction completely new story would be presented in each episode, with new actors, settings, and situations. The only continuing link was the producers, the genre, and the series title. The first series of this kind was "Tales of Tomorrow" running for 85 episodes, between 1951–53, it was meant to be the first science fiction show for adults. The next popular series was "Science Fiction Theatre", a syndicated series that ran for 78 episodes between 1955–57. Two years after its run finished, a much more popular and influential program in the same vein debuted on the CBS Network: "The Twilight Zone", hosted