Writer/Director David Robert Mitchell’s It Follows hits many of the notes that are by now (beyond) familiar to horror aficionados — it is, in part, a good summary of the horror movie tropes of the last 25 years or so. The film includes a relentless stalker, the thematization of teenage sexuality, a handful of fake-out jump scares, unseen-but-material malevolent beings, scary children, heroes who make terrible decisions and a moment of shocking gore. But this rather typical assemblage of tropes and characters belies the film’s originality, which consists more in the effective and often unique way these elements are deployed.