Arthouse horror is on a tear right now, and it’s no secret. One of the most inspiring movements in American cinema right now, modern classics like “Hereditary,” “Get Out,” “The Witch,” “It Follows,” et al. have reinvigorated a genre blunted by the cheap slasher films of the ’80s and ’90s and sparked something of a movement, thoughtful, emotionally bruising and sometimes glacially paced horror. Who knows, look back in 10 years, and cinema historians may find an even deeper correlation that we can see to our toxic, uncertain times, and this cinema of unease and collective trauma.