Halfway into this, you think: the mental aftermaths of losing a loved one, even for an historically schizophrenic family (cleverly blurring the line between delusion and reality) may be ‘scarily’ traumatic ... but that hardly constitutes horror. Well, think again. Combined with ingenious audiovisual cues, the way the final half-hour suddenly flips the established setup on its head and delivers its unexpected and creepy ending, you’d imagine this should be taught in film school as 'horror film-making 101'. Entirely relying on viewer intelligence, Hereditary pulls it off. It had been a long time since I’d been scared in the theater.