From The Prisoner in the 1960's to the more recent Heroes and Lost, a group of television series with strong elements of fantasy have achieved cult status. Focusing on eight such series, this work analyzes their respective innovations and influences. Assessing the strategies used to promote "cult" appeal, it also appraises increased opportunities for interaction between series creators and fans and evaluates how television fantasy has utilized transmedia storytelling. Notable changes within broadcasting are discussed to explain how challenging long-form dramas have emerged, and why telefantasy has transcended niche status to enjoy significant prominence and popularity.