Divorce is never easy, especially when there are children involved.

That's the case in "The Lodge," a horror film that screened this weekend at Fantastic Fest. For Aidan (Jaeden Martell, "It") and Mia (Lia McHugh, recently cast in Marvel's "The Eternals"), they are simply far more connected to their mother (Alicia Silverstone in a blink-and-you'll-miss-her performance) than their father, Richard (Richard Armitage).

The family is torn apart after Richard reveals plans to leave his wife for Grace (a brilliant Riley Keough), a woman who comes with plenty of her own baggage, as she was the lone survivor of a cult suicide pact led by her father when she was just 12. Grace has tried to put that past behind her as an adult, but her path forward would be nearly impossible without the assistance of medication.

The kids, well, they just don't understand. Not only do they not even try to get to know Grace, they hate their father for breaking up their family and blame her for their pain. When Richard suggests that he is going to marry Grace and wants her to join them at the family's remotely situated guest house for Christmas (something that was an annual retreat with their mom), Aidan and Mia are less than enthused.

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To add insult to injury, Richard decides to drive them all up there to the house and then go back toward the city to work for a few extra days before returning on Christmas. He hopes this will force the kids to spend time with Grace and start to fall in love with her.

If you've seen the trailer or know anything about horror moves, you can probably guess that things do not go exactly to his plan.

Austrian co-directors Veronika Franz and Severin Fiala ("Goodnight Mommy") make their English-language debut with this masterfully shot thriller that revels in darkness and uncomfortable silences. To say more about how the story unfolds would venture into spoiler territory, so let's focus on what makes it all so unforgettably creepy.

Franz and Fiala make us uneasy from the very start. A close-up of a glass with a dissolving Alka-Seltzer tablet illustrates how the tension is just bubbling under the surface early on. As we move out to the winter lodge home (the layout of which is creepily foreshadowed thanks to an enormous dollhouse replica of it in Mia's bedroom), it becomes difficult to see how the family dynamic is going to improve on this little trip.

The child actors are good and hold their own as the story progresses, but it's Keough who owns every frame of every scene she's in. Her cinematic unraveling is subtle, but powerful.

Overall, this is probably too slow and slightly overlong to really connect with general audiences, but fans of recent genre hits like "The Witch" and "Hereditary" should feel right at home in the cold and quiet.

"The Lodge" screens again 8 p.m. Sept. 23 at Fantastic Fest. Neon picked this up for distribution after it premiered at Sundance earlier this year. It was initially scheduled to come out in November, but it appears as though they are pushing the U.S. release until Feb. 7, 2020.

Grade: B