The ‘Anyone But You’ and ‘White Lotus’ actress plays an American nun who moves to an Italian convent filled with sinister secrets.

When the police stop the young woman on her way to the convent in the Italian countryside, they wonder why such a person would choose to become a nun. As they rummage through her luggage — a search conducted because she has no return ticket — they ask, in English, if joining a convent was a difficult choice. The woman scans their faces in confusion before responding: “I don’t see it as a decision,” she says with bitter force. 

Cecilia arrives at the Italian convent, a creepy locale about which we also learn very little, ready to renew her vows to God. The eerie aesthetics coupled with a few hostile encounters quickly set the mood. The church sits in an isolated part of a hilly expanse in the middle of nowhere, perpetually surrounded by a parade of gray clouds. Production designer Adam Reamer’s faithful rendition of Catholic interiors — wood paneling, candle lights and crosses adorning each wall — is chilling enough, and Francesca Maria Brunori’s costumes create a haunting uniformity among the nuns.

Immaculate starts as an intimately observed thriller before leaning into better suited B-movie horror conventions. Cecilia’s introduction to life at the convent is neatly wrapped into a few montages, which show her and the other nuns learning to fold laundry, care for the elderly women in the hospice program and cleanly kill a chicken. The new nun becomes friends with Sister Mary (The White Lotus season two’s Simona Tabasco), a brash and defiant woman who joined the convent to escape an abusive relationship. Unlike Cecila, Mary is openly skeptical about the goings-on at the church, and her outburst during a pivotal moment is one of the few energetic moments of the film. Otherwise, Immaculate relies on jump scares to jolt audiences out of its slumber-inducing plot. 

Even Sweeney can’t save the film. The actress, who also serves as a producer with her company Fifty-Fifty Films, has had an impressive streak of performances from Cassie in Euphoria to her Emmy-nominated portrayal of a monotone-voiced, spoiled adolescent in the first season of The White Lotus. More recently, she demonstrated real range in Reality, investing NSA whistleblower Reality Winner with a quiet force.

It’s a shame that there are only glimmers of that in Immaculate. Cecilia, whether because of the screenplay or the performance, never comes off as a fully coherent character. Soon after her arrival, the nun finds out that she’s pregnant — an immaculate conception considering that she’s never had sex. Although Sweeney is more persuasive in the latter half of the film, when the trauma of pregnancy turns Cecilia into an avenging nun, the early sweetness and naïveté of her character is too cloying to track with her sudden personality shift.