The project was announced in October 2017, with Riley Keough joining the cast of the film and Franz and Fiala directing from a screenplay they wrote alongside Sergio Casci.

Laura Hall takes her own life after her estranged husband Richard informs her he plans to marry Grace Marshall, a woman he met while researching a book about an extremist cult.

Aiden and Mia uncover Grace's past, including video footage of the cult, showing the deceased followers draped in purple silk with duct tape across their mouths reading "sin."

At the lodge, the children act hostile toward Grace and refuse efforts to bond with her, even after Richard departs back to the city for a work obligation.

Grace's unease is compounded by the abundance of Catholic iconography (including a reproduction of the Virgin Annunciate by Antonello da Messina) in the cabin, which causes her to have nightmares about her father.

In the morning, Grace awakens to discover that her belongings – including her clothing, psychiatric medication, and pet dog – are missing, as well as all the food and Christmas decorations.

Buried in the snow, she discovers a photo of Aiden and Mia in a memorial frame, and inside, finds the children praying over a newspaper article detailing the deaths of all three from carbon monoxide poisoning on December 22, 2019.

Worried she might die of exposure, the children finally admit that they have been gaslighting her the entire time, having drugged her, hidden their possessions in a crawlspace, faked the hanging, and played recordings of her father's sermons via a wireless speaker.

With their own phones dead at last, the children unsuccessfully attempt to start the generator and bring Grace her medication, but find her convinced that they are in purgatory and must do penance to be accepted by God and ascend to heaven.

They hide in the attic but Grace confronts them in the morning, insisting they must "sacrifice something for the Lord" and "free themselves from idols" before setting Mia's doll on fire.

Convinced it is a sign of her incapacity of dying for being in the afterlife, she turns the gun and opens fire at Richard, shooting him in the head and killing him.

Grace forces the children back into the lodge, where she seats them at the dinner table with their father's corpse and sings Nearer, My God, to Thee.

[13] Fiala elaborated on the decision to shoot chronologically: "[Riley] was worried that the journey her character takes was a very difficult one, because she has to hit every mark in a way that it still is plausible.

[13] While shooting the interiors, Bakatakis, Franz, and Fiala deliberately chose to not frame shots at eye-level, instead opting for angles positioned from above or below the actors.

The site's critics consensus reads: "Led by an impressive Riley Keough performance, The Lodge should prove a suitably unsettling destination for fans of darkly atmospheric horror.

[21] Dennis Harvey of Variety wrote that "The Lodge may be best taken on the same terms as '60s/early '70s Italian giallos, with their somewhat random manipulations of plot and character logic in service of atmospheric shocks.

"[24] Benjamin Lee, writing for The Guardian, awarded the film four out of five stars, alternately praising it as "an accomplished beast: poking, prodding and teasing as it throws out potential twists before settling on the most devastating one of all.