'Saint Maud' is a brutal and terrifying thriller you won't want to miss

• "Saint Maud" focuses on a young nurse who's fixated on saving her dying patient's soul.
• Maud's religious mania soon becomes something darker, leading to a chilling and violent conclusion.
• A24's new horror film premieres on Epix on February 12 at 8 p.m. ET/PT.

Catholic "mortification" of the flesh - or wounds inflicted on oneself as a means of penance and punishment - is a practice that goes back thousands of years, starting with several Catholic saints, and continuing on up through the 1950s.

Even though it's now generally discouraged by both the Catholic church and most of its devotees, some sects still engage in this brutal practice of self-harm in the name of religion.

Enter "Saint Maud," the new horror film from Welsh director Rose Glass that focuses on a devout young woman named Maud (the wonderful Morfydd Clark) engaging in vicious self-punishment while caring for - and subsequently being tormented by -Amanda (Jennifer Ehle), a former dancer dying from cancer.

In addition to growing more and more devoted to her faith, Maud is also trying to save Amanda's soul before she dies from her illness.

Taking the archaic religious practice to a whole new level of depravity, the film is both a gory psychological horror film and an exploration of faith - and the disasters that can occur when devotion reaches new heights.

The film draws inspiration from a bizarre, real-life Catholic tradition

While the concept of self-flagellation seems right out of the Middle Ages (which is when it's believed to have originated), it's still something that's practiced by a few ultra-devout Catholics today, although the practice has grown increasingly rare.

While Maud never expressly identifies herself as a Catholic in the film, her tendency to self-punish (including kneeling on grits) seems rooted in the practice of self-flagellation, although Maud definitely takes it to the extreme.

As she becomes more and more devout in her faith, however, Maud begins to lose touch with reality and her sense of self - culminating in a brutal finale that includes sexual assault, murder, and self-immolation.

'Saint Maud' offers a compelling commentary on the dangerous affects of unadulterated faith

"Saint Maud" is definitely not for the faint of heart.

Even though the movie starts slow (much like 2018's "Hereditary"), it quickly picks up and delivers some spine-chilling moments of true terror that made me jump out of my seat.

Most of the horror comes from Maud, who becomes increasingly committed to her mission of saving Amanda's soul - even after she was cruelly teased and rebuked for her faith by Amanda during a party.

But as Maud's commitment to Amanda's spirit grows, so does her devotion to her religion. While earlier in the film, Maud was content with prayer and good deeds, she quickly graduates to violent instances of religious self-harm, including burning her hand on the stove and later ripping off the blistered skin in a particularly squirm-inducing sequence.

One of the most cringeworthy scenes comes after a desperate Maud resumes her past "sinful" behavior, including getting drunk and having sex with strangers.

The next morning, however, Maud's religious zeal returns - and after placing a card full of thumbtacks in each one of her shoes, she puts them on, and spends the rest of her day walking around in agony. The sound mixing here is particularly disturbing, as each squish of the tacks in Maud's feet are heard clearly.

But while the film has plenty of gory moments, an exploration of religious devotion forms the heart of the story. Maud, it's implied, used to be a troubled party girl who frequently picked up men at bars, and was even fired from the hospital she worked at for (inadvertently?) killing a patient.

In her newfound religious zeal, however, she's no better, resorting to self-harm and, eventually, murder, all in the name of her faith. And during her final confrontation with Amanda, Maud's faith is put to the test - ultimately resulting in several gruesome deaths.

The movie, overall, is fantastic - but those who are squeamish might want to stay away.

In case it wasn't clear already, "Saint Maud" is a pretty gory movie - but it's less pure gore, as in the "Saw" movies, and more slow-building body horror like in Takashi Miike's "The Audition."

Seasoned horror fans shouldn't have any trouble stomaching Maud's increasingly deranged forms of corporal punishment, but those who are especially sensitive to blood-and-guts type of horror films might want to check out something else.

The bottom line: 'Saint Maud' is a terrifying and original film that doesn't shy away from showing the dark side of religion.

It takes a lot to scare me (a pretty seasoned horror fan), but I was sleeping with the lights on after watching "Saint Maud."

That being said, it's easily one of the best films I've seen in the past year - and the best new horror movie I've had the pleasure of watching since 2019's "Midsommar."

Gory, gruesome, and gripping all at once, "Saint Maud" is a powerful exploration of the affects of blind faith - and the lengths one woman will go through to prove herself to her creator.

Anchored by stellar performances from Clark and Ehle, it's an eerie but altogether absorbing film by one of horror's most promising new directors. Don't miss it.

Grade: A+

"Saint Maud" premieres on Epix on February 12 at 8 p.m. ET/PT. You can watch the trailer below.