This amusing horror/fantasy (/comedy?), written by and starring the co-directors, bears a striking resemblance to this year’s considerably more ponderous Annihilation. What distinguishes The Endless is its sense of humor, dryly prodding both the expectations of its genre framework and the familial combativeness unique to obstinate, nitwit brothers. (Moorhead and Benson are pretty smart about creeping dread but very smart about feeling frustrated with your family.) The film sometimes loses track of all its threads, but it’s made with care and intelligence and an edge of impatience with the kinds of pitfalls that often compromise similar ventures into stories of cult survivors, cult infatuation, mysterious big bads, and even the Primer-esque twist that clarifies at around the hour mark. Not an altogether success – digressions often resemble fragments of a long, layered novel – but if it wobbles some, it ends well and the Moorhead-Benson duo exhibit a knack for provoking unease with vivid, oddball images.