Rose Glass writes and directs an unforgettably creepy story about a troubled young nurse’s efforts to save her patient’s soul.

When it comes to suffering, no one does it like Catholics. Consider Opus Dei, the secretive branch of Catholicism that still allegedly practices self-flagellation, or the hardcore worshipers who recreate Christ’s crucifixion every Easter, rather than dyeing eggs or baking a ham. Even when mortification of the flesh isn’t involved, no other religion promotes the idea of misery as the pathway to salvation. Rose Glass’s nightmarish Saint Maud digs deep into the pathology of that mindset, and is something you won’t likely forget for a long time.

Maud (Morfydd Clark) is a palliative care nurse, the most lonely and depressing of jobs. Without friends or family, all she has is her work, and her close, intimate relationship with God. Maud redefines the phrase “zeal of the newly converted,” addressing God as if she’s writing in a journal, and all but demanding that He give her some sense of purpose in the world, rather than seeking it out herself. She also engages in increasingly horrifying acts of self-injury as worship, including kneeling on gravel, burning herself (and picking the scab, in one stomach-clenching scene), and walking around with thumbtacks in her shoes. The curious thing is that we never see Maud going to church, consulting with a priest, or even reading the Bible. This strange sort of worship by way of torture seems to be something she’s come up with all on her own.

One assumes Maud got into nursing not because she wanted to help people, exactly, but because it was the most saintly job she could take without actually joining a convent. Her newest assignment brings her into the home of Amanda Kohl (Jennifer Ehle), a chain-smoking ex-dancer who’s dying of lymphoma. From the moment Maud enters Amanda’s employ, their relationship is complicated. Though Amanda is twice Maud’s age, she’s the one whose destructive behavior must be kept in check, while Maud, pinch-faced and frumpy, tries to keep bad influences away from her. There’s also an undercurrent of something else there, a feeling that Amanda may recognize, but Maud doesn’t (or refuses to), even when it results in lingering stares and hands “accidentally” brushing against each other.

Mostly, Maud believes that God has brought her to Amanda’s home to save her. With the kind of arrogance agnostics only wish they had, Maud considers herself to be a savior, and will bring you into the Kingdom of Heaven, kicking and screaming if necessary. Amanda is both fascinated and amused by Maud’s belief that God is both in and around her, and Maud comes on hard, gasping and rolling her eyes back in nothing short of sexual ecstasy when she feels Him near. It’s obvious that the bitter, cynical (and rightfully so) Amanda is at first humoring Maud, then outright making fun of her, but Maud is maddeningly short-sighted. This is what God has chosen her to do, and she’s going to do it.

Saint Maud is something you won’t likely forget for a long time.

When converting Amanda proves to not be easy, Maud’s faith is immediately shaken. She’s the kind of dangerous Christian who believes that there’s a heavenly reward just for being a decent person, and when she doesn’t get that reward right away, she reacts with confusion and anger. If anything, God’s reward for her selfless devotion seems to be constantly reminding her of her troubled past. But this is all she has, and she clings to her beliefs (muddled and damaging as they are) as she makes one last ditch effort to get Amanda’s soul to a better place.

I’m not sure if Saint Maud will resonate as much with atheists and the non-religious. However, if you’ve ever gone through a pious period of your life, believing that your virtuousness would be rewarded in some tangible way, it’s going to shake you up. We don’t know how Maud came to be “saved” herself, but she’s been fed a toxic message that she must prove herself worthy to God by suffering. It may seem bizarre, but how far off is it from the idea that it was “God’s will” that a child die of cancer, or a bus goes off a highway, killing everyone in it? It’s supposed to be comforting, the idea that God just makes these decisions sometimes, and they’re for the best, whether we like them or not. If nothing else, it emphasizes the nonsensicalness of organized religion.

Maud’s questioning of her faith is normal (and, indeed, why so many people ultimately fall away from their church). But she’s so dug in, so deeply reliant on it to escape from loneliness, that, rather than direct her energy towards something more fulfilling, she makes herself an example of what a “good” Catholic should be: rending her flesh, looking for signs, always awaiting His next instructions.

As Maud, Morfydd Clark will be remembered as one of the great spooky horror movie performances. Other than an incident during a previous nursing assignment, we know almost nothing of her past life. She seems to have dropped from the sky without any guidance on how to be a normal person, as exhibited in a scene where she tries to mingle with a group of people her own age at a bar. She’s fragile, but there’s something about her that you wouldn’t want to mess with either. Jennifer Ehle as Amanda is excellent too, also fragile in her failing body, but sharp-minded and observant. Maud and Amanda’s chemistry is fascinating, something other than nurse-patient from the start. When Amanda initially goes along with Maud’s claims that she can feel God’s presence, it feels like a seduction, and another test of Maud’s faith.

With a Hereditary-level bleak ending, Saint Maud is relentless in its message that there’s no hope in salvation. Maud’s sacrifices and self-injury are in vain. She is punished for her arrogance, in the same way that she believes Amanda is being punished for her lack of faith. Either way, we all end up in the same place.

Saint Maud premieres on Epix February 12th.

Saint Maud Trailer: