Telefantasy offers the first book length study to consider the place of fantasy, science fiction, and horror dramas in the history of British and US television. Looking at two periods (the 1950s/60s and the 1990s/2000s) when telefantasy has been particularly prevalent on television, this book provides detailed historical accounts of the production of key 'telefantasy' programmes: the Quatermass serials, The Prisoner, Star Trek, The X-Files, Buffy the Vampire Slayer, and Randall and Hopkirk (Deceased). Each case study is situated in relation to the development of the British and US television industries and the regulatory and critical discourses surrounding them, offering a new understanding of the individual programmes and the historical development of television as a medium. By bringing together a range of fantasy dramas and asking what they offered to television producers, Telefantasy challenges the previous understanding of these programmes as 'unique' cultural phenomena, and asks whether telefantasy can be understood as a genre. Through this analysis, Telefantasy argues that 'the fantastic' is a particularly rich area for re-examining the central assumptions about the aesthetics of television. These tales of alien invasion, futuristic space travel, and vampire slaying challenge the dominant notion that television is an intimate medium unsuited to the display of visual style. Telefantasy engages with current debates about television history, genre, narrative, and spectator theory, while providing case studies that will be of interest to students of television and fans of telefantasy.