Few could have predicted the enduring affection inspired by Joss Whedon's television series, Buffy the Vampire Slayer. With its origins in a script Whedon wrote for a 1992 feature film of the same name, the series far outpaced its source material, gathering a devoted audience that remains loyal to the show more than a decade after it left the airwaves. Heralded for its use of smart, funny and emotionally resonant narrative; subversive and feminist...