Starring Riley Keough. Rated 14A

In the au courant field of classy horror pics, this week’s entry comes with a pedigree. Behind the camera is the Goodnight Mommy team of Severin Fiala and Veronika Franz. In front we have the increasingly impressive Riley Keough. She plays Grace, the sole survivor at 12 of a suicide cult, about to marry journalist Richard (Richard Armitage), who wrote the book on the apocalyptic religious sect. This news isn’t exactly welcomed by his ex, Laura (Alicia Silverstone), who promptly stages her own preemptive exit.

Understandably, kids Aiden and Mia (Jaeden Martell and Lia McHugh) are also a little miffed about all this. Dad tries to mitigate by bundling everybody up for some family-building exercises at the remote, snow-locked lodge of the title. And that’s when things start to unravel for fragile old Grace, already concealing her meds from Richard and flailing in her attempts to connect with the offspring. When he’s called back to the city for work, she goes off the rails, and so does the film. Either Grace is going nuts, or she’s being gaslighted, or everybody has died and gone to hell. It might be all three.

For those of us who generally prefer delirium over the just-so tidiness of a film like Us, it might not matter too much what exactly is going on here, even when the film starts to strain under its own contrivances. Where The Lodge succeeds is in its patient atmosphere-building and downer psychedelic style, delivering neatly staged and effective shocks like Grace’s plunge into an icy lake, along with grandiose bursts of cathedral-sized organ to punctuate her waking nightmare. Also impressive is the use of location, flipping between the snow-blind landscape of Quebec at its most wintry and the gloomy claustrophobia of the lodge itself, combining into a tense dialectic of isolation and madness.

Oddly, there’s a big moment that echoes the nastiest scene in The House That Jack Built, Keough’s last genre effort. She was dispatched too soon in that film. Here, luckily for us, we’re holed up with her until the bitterest of endings.