Goodnight Mommy is a bone-chilling, morose, and subtle tale of traumatic extremities. Directing-writing duo Veronika Franz & Severin Fiala understand how to scare viewers out of their wits: with upticks in cruelty at a gradually discomforting pace, even if things shuffle too long to maintain consistent, intriguing frights. In an isolated bit of Austrian greeneries, a woman (Suzanne Wuest) comes home to her twin sons, Elias (Elias Schwarz) and Lukas (Lukas Schwarz), after cosmetic surgery rendering her face bandaged, minus her eyes and lips. Expecting their usually warm and affectionate mother, twins Elias and Lukas receive the opposite; cold, abrasive, rule-enacting, and sometimes physically abusive, their mother is not who they remember. The brothers thus suspect that this woman is not their real mother. To confirm their suspicions, they investigate, looking at old photos and voice recordings before planning and executing various pranks and tests on their suspect. However, as their gags become increasingly violent, constrictive and tortorous—even if the big reveal becomes apparent too early—viewers come top wince as they realize something else is amiss before a truly punishing finale.

Goodnight Mommy is a movie about people not coping properly with massive traumas. Without spoiling, it’s immediately clear this small family’s livelihoods have shifted dramatically, and no party is entirely untraumatized. As cameras slowly pan over the trio’s large, empty house, whether it focuses on the brothers playing with each other or their mother watching from a distance, the family feels uncomfortably distant from one another. The kids giggle and grin when together, but when their Mom enters, it’s nothing but silence and a bit of fear. As they talk, why the boys are so fearful of their supposed mom vividly shows: she’s authoritarian in her rule-making and avoidant in her once affectionate, warm outlook the boys remember. For example, one of the first things she tells her sons when she returns is to obey her needing rest and silence: “This is important. Look at me.… The doctor said I need rest. And I expect your support. There’ll be some new rules,” she starkly commands, dagger-eyed and almost angry that she has to explain these things at all. Upon hearing old recordings of her telling the boys how much she loves them, it’s hard not to at least understand why her sons think she may not be who she says she is. Such a strict, standoffish tone infinitely adds to an already creepy environment, which only intensifies as she seems to cold shoulder one kid, beats the other for acknowledging the ignored one, and (maybe) kills an injured cat they find and take in on their own to nurse back to health.

Once the boys take control of the situation, tension rises triply and the terror doubly so. While the big reveal comes way too early—significantly diluting the suspense halfway through, even if it helpfully switches the protagonist-antagonist roles for viewers—the possibility of the boys’ interrogative techniques and the methods they eventually use keep things yelp-worthy. With help from a sinister score, bone-chilling performances from the Schwarz twins, and a few metaphors of stripped innocence—“Can you count the stars so brightly / Twinkle in the midnight sky?” the boys sing, circling back to the classic hymn Can You Count the Stars? shown in the film’s opener as they torture their now clearly tied-down mother—Goodnight Mommy demonstrates two core familial themes: their mom failed the boys, and kids in general take after their parents, even if it’s too the extreme here. Everything they do to their Mom is an extreme of what she does to them earlier: she beat Elias and recorded him as she commanded “Repeat 10 times that you won’t listen yo your brother,” so they tie her down and equally humiliate her whilst saying “our mom wouldn’t do that.” Whatever actually happened, she didn’t handle the boys’ needs at all, rendering them abandoned vessels of rage and sponges of their mom’s—which leads to an equally sad, punishing, and horrifying conclusion that probably leaves the family off in a much better state of living than they were immediately before.

Thus, while an overly slow pace can drag things and that early revelation lightens the load, Goodnight Mommy is a frightful, horrific, and depressing piece about familial failure and traumatic reaction. For horror fans, it’s a slow-burn must watch.

Screens Saturday, 8/23, 11:59 p.m. @ Coolidge Corner Theatre
Part of the ongoing repertory series: The Kids Are NOT Alright