For ‘Sacred Creatures’ director Frieda Luk, belief can be comforting, ridiculous, exhilarating, and hard to explain. ‘I’m really fascinated by when people believe in something,’ she tells Variety. ‘One person believes in something, and then a group of people, and then it slowly becomes this massive phenomenon. It goes viral.’

Luk’s debut feature, which world premieres in competition at the Edinburgh International Film Festival, follows three estranged siblings reuniting in rural Italy after middle sister Miriam (Olivia Luccardi) is released from psychiatric treatment following an experience she understands as a spiritual awakening rather than a breakdown.

Related to the film’s theme of belief, Luk points out, ‘Miriam has agency. She knows herself and she makes choices. However, when she becomes a figure that people rally around, people are imbuing her with meaning. When she becomes abstract, she no longer controls the message.’

The uncertainty in the film extends to its tone, which slips between psychological drama, comedy, and magical realism without settling comfortably into any of them. For Luk, the tonal slipperiness developed naturally from writing. ‘I set up the situation and these characters, and as I’m writing, I’m following what they’re doing. What I’m waiting for is how they surprise me,’ she says.

One influence on Luk’s approach was Marco Ferreri’s ‘La Grande Bouffe,’ the grotesque story of four men attempting to eat themselves to death. ‘The comedy is following through that premise in a serious way, because if you actually are going to eat yourself to death, you’re going to have gastrointestinal problems,’ Luk says. ‘It’s also very silly. It never takes itself too seriously.’

Italian cinema was integral to ‘Sacred Creatures’ from the start. Luk points to films of the 1970s, admiring their willingness to move between modes contemporary cinema can sometimes keep separate. ‘A lot of the ’70s movies, especially European ones, are completely in between genres.’

Luccardi was similarly keen to avoid reducing Miriam to a diagnosis. ‘She is healing from the lack of belief from people and everyone thinking that something was wrong with her,’ Luccardi explains, adding that Miriam feels ‘meant for something greater.’

There was another, less metaphysical piece of direction that unlocked the character: Luk told her Miriam was like a cat. ‘She’s very much like: ‘I’m letting you in on my terms. No, I actually don’t want you to touch me. I want to be a pet, but not like that,’

Luk wanted the dress to be ‘kind of ridiculous looking, but also kind of chic,’ something that would ‘take up some space’ without seeming entirely out of place. ‘Miriam is new and a little ridiculous,’ she says, with its uncontained ‘fluffiness’ signalling ‘an irreverence to what has come before.’

The surrounding family remain skeptical of their sister’s burgeoning allure to those around her. Luk, an only child who grew up surrounded by cousins, was amused by the way relatives can inhabit incompatible versions of the same history. ‘They’re always competing,’ she says.

The instinct of creating a story that makes life easier to comprehend ultimately expands beyond the siblings. Luk grew up without religion, but many childhood friends were religious and invited her to churches and youth groups. Watching from the outside, she was intrigued by their ability to surrender themselves to faith.

‘I would watch them read a text and believe in that text and treat it like this holy thing,’ she recalls. ‘It was really hard for me to give myself over to something like that.’

At Catholic services, she found herself captivated by the incense, clothing, and ceremony. ‘I was like: ‘This is so fun and theatrical. I can see how it could be really comforting,’ she says. ‘There’s a community-oriented spirit to it. Being a fan of a big sport is kind of fun. Yelling at a team is fun.’

The director began thinking about fandoms, sports, and social media with much the same curiosity. What separates a few people who regularly gather from a movement? ‘What if people hung out, and then that becomes a movement?’ she says. ‘A few people hang out, and then more people hang out. Then you do it regularly, and what happens?’

The film is shot in Piedmont and Italy provided a fertile landscape for those questions. Luk recalls seeing reports about a teenage protester and wondering why there couldn’t be a patron saint for protest, and what the origin story of a new saint might look like.

But after all that construction of a film, a family history, a faith, and perhaps even a saint, the director isn’t interested in providing audiences with a final answer about Miriam. ‘I want people to come away examining why they believe in something and how,’ she says, ‘and that there is a pleasure in believing something.’

‘You never know if you are right or you are wrong. You might be wrong.’

Or, as Luccardi puts it: ‘You never know if someone’s crazy or if someone’s enlightened. Who knows?’ It’s a fine line.