This is a lesson on how to convey cosmic horror, which needs to be experienced rather than explained. Most attempts at cosmic horror fail because of the human need for an explanation. You can’t explain the unknowable. Once you concretize and categorize a thing, it loses its ability to spark awe and wonder. No Cthulhus and Yog Sothoths wandering through here. The Endless stumbles toward the end when we learn the destiny of the cult, but it’s a small stumble that doesn’t mitigate the the pervasive, growing unease that permeates most of the film. This is the kind of film that frustrates hidebound imaginations because it doesn’t lay everything out for you tied up in a pretty ribbon. The viewer’s need to infer helps create the horror and is what makes it work. (As opposed to works that never really knew where they were going in the first place.) I’m hardly an elitist. I like jump scares and gross-outs as much as the next guy, but if you need those to define a horror film, skip this. It’s not for you.