What becomes of individuals who disappear within isolated National Parks? A brother and sister, portrayed by Hattie Smith and Zac Titus, venture into a National Park with some companions to locate their missing sibling in the Far West—and increasingly odd occurrences begin. Do any of them manage to return safely? "The Axiom," released in 2018, fundamentally operates as a cabin-in-the-woods story, but its advers…