How did this happen? Its like someone, while absently pondering mash-ups of horror sub-genres, put The Ring’s pass-it-on curse next to Halloween’s teenage body count and stumbled upon a Tutankhamun’s tomb of treasures. It Follows‘s simple premise of sexually transmitted doom magically disgorges a gripping synthesis of almost every classic horror trope – vampires, stalkers, murderers, rapists, slow zombies, terminators, body snatchers, strangers, demons, ghosts, succubi – all are touched upon as is a chillingly sober appraisal of cold, impulsive, treacherous, teenage sex. Tone and cast are faultless. Maybe it’s not baked perfectly all the way through but who cares?