Hallowarrior works because it earns its central conceit rather than just announcing it. A disease has killed most of humanity; 16-year-old Pumpkin has been alone in her rural family home for nearly four years, since she was 12. That backstory isn't set dressing — it does real mechanical work. It explains why she makes some decisions that look naive, why she makes other decisions that look almost unnervingly competent, and why neither register feels like a screenwriter's convenience. Milly Shapiro, whose feature debut was as the unsettling younger sister in Ari Aster's Hereditary (2018), is in almost every scene, and the film lives and dies by that choice. She's good enough that it doesn't die. Pumpkin is an arresting presence — simultaneously underdeveloped in the ways a sheltered teenager would be and overdeveloped in the ways a survival situation demands. Shapiro holds that contradiction without underlining it. The premise's hinge — Pumpkin broadcasts a Halloween celebration invitation and attracts the wrong people — is functional genre scaffolding, not a twist. The film knows you know where this is going. What it's betting on is atmosphere, production design, and character specificity rather than surprise. The production design pays off: the film moves between cosy autumnal cottagecore and something closer to the Bates Motel's airless dread, and the gear-shift works. Shannyn Sossamon leads the threat as Thalia, and the film is smart enough not to over-explain her or her crew. Director Ben Sottak, whose background is in short films, shows the control you'd expect from that training — precise compositions, a willingness to let silence do work — alongside the occasional pacing unevenness you'd expect from a first feature. The Home Alone comparison in the marketing is accurate but slightly misleading. The booby-trap logic is there, but Hallowarrior is less interested in escalating gags than in the sustained unease of a girl defending a home that is all she has left. The horror payoff is inventive enough that it earns the slow build, though viewers who want their shocks front-loaded will spend the first act impatiently. This is a debut feature that knows what it is and mostly delivers it. It doesn't overreach — there's no pretension to saying something Large about grief or civilization — but within its chosen scope it's significantly better-crafted than the genre average. Sottak is worth watching. Shapiro, who had an unusual career detour between Hereditary and this, has now confirmed that the first performance wasn't luck.