These films are patient and airless, taunting you with simple, appealing horror premises that feel stretched and subdued under all the whispering, nasty atmosphere. Perkins hit the mainstream with Longlegs and especially The Monkey, last year’s ridiculous horror farce. How was Keeper received upon release? It boils everything we know about “elevated horror” down to its essential tenets, and its plain, no-frills execution may be the final word on the trend. Keeper is so much a checklist of the stripped-back, inward-looking, and subversive tenets of the “elevated horror” genre that it was easy to overlook.