This image was taken from the official trailer for “The Wonder,” distributed by Netflix.

Picture a thaumatrope — an optical, disc-shaped toy with two images on either side that blend together when the attached string is pulled and the disc spins — with an image of a caged bird on one side, and the same bird, uncaged, on the other. When it spins, the bird alternates from inside and outside the cage. Is the bird trapped or free? In or out? Sebastián Lelio’s “The Wonder” visualizes this scene — this question — prompting the viewer to contemplate what they choose to believe.

“The Wonder” opens on a house set before the camera slowly pans to reveal an empty soundstage. A disembodied narrator (Niamh Algar, “The Virtues”) with a warning tone breaks the silence to deliver a message to the audience: “The people you are about to meet — the characters — believe in their stories with complete devotion. We are nothing without stories. And so we invite you to believe in this one.” Belief is one of the film’s central themes, and the abnormal prologue serves to set the uneasy tone of “The Wonder” and draw in a willing audience. 

“The Wonder” is adapted from Emma Donoghue’s book of the same name and inspired by the Fasting Girl phenomenon of the Victorian era, in which girls would starve themselves and claim faith gave them life. This story opens on a ship from England to Ireland, on which travels nurse Lib Wright (Florence Pugh, “Don’t Worry Darling”). A local council has called her to investigate an oddity: Professed a holy miracle by the religious community, a young girl named Anna O’Donnell (Kíla Lord Cassidy, “The Doorman”) claims she has not eaten in four months.

The council assigns Sister Michael (Josie Walker, “Belfast”) to Anna’s case alongside Lib and tasks them both with conducting a watch over the girl to report their separate observations. Upon Lib’s examination of Anna, she curiously appears to be in good health. Journalist William Byrne (Tom Burke, “The Souvenir Part II”) travels to the rural village to report on the miraculous story, sharing mutual suspicion of Anna’s reverent family with Lib. Anna’s mother, Rosaleen (Elaine Cassidy, “The Others”), denies accusations of deceit and Anna insists she has been sustained only by manna from heaven. However, Lib soon discovers how Anna has survived these four months and the grim reason behind this madness.

Anna breaks the fourth wall as she seems to look into the camera a few times during the film. It’s as if she is, in fact, chosen and this is her story, and she is aware of her audience. This continues the theme of belief in “The Wonder,” as her subtle affirmation that this is indeed a work of fiction emphasizes the power of faith. The meta aspects of this film parallel the dichotomy between religion and reason evident in this story. The headstrong council, the devout nun, the skeptical journalist, Anna’s religious family, the desperate nurse and Anna herself clash with great force. As Lib begs for action to save Anna’s life, she is left hopeless as Anna’s own mother refuses to believe she deserves saving. 

Aesthetically similar to a Robert Eggers (“The Northman”) film, “The Wonder” has the look of a gritty, gray horror period drama. The film is stripped of anything ornate and denies its characters and rural Ireland any superficial filter. The visual storytelling relies on the bleak nature that surrounds the uninviting O’Donnell home and the cool tones that dull the already monotonous costume and set design, reminiscent of Cary Joji Fukunaga’s 2011 film adaptation of Charlotte Brontë’s “Jane Eyre.”

A true psychological film, “The Wonder” is backed by its extraterrestrial score, composed by Matthew Herbert (“Disobedience”), which augments the film’s disturbing nature. A vocal motif is found throughout the soundtrack, complemented by strings and occasional percussion, tuned to high and low octaves that often sound alien-like and cavernous. The unnerving arrangements possess qualities evocative of the theremin — “eerie ethereal” and “serene ethereal,” according to the subtitles — as if the sounds of space can be found in these hidden, unlikely parts of the 19th-century Irish countryside. Herbert is keenly aware of the emotional journey Lib and Anna embark on, as the music evolves from uncomfortable to breathtaking and summons chills from the audience. 

Pugh delivers a stunning performance, unflinching and instinctive in her role as Lib. The film alludes to the loss of Lib’s own young child, which plays into the underlying theme of grief and fuels her unwavering determination to save Anna. Despite the horrific circumstances of “The Wonder,” the film is wonderfully poignant and emotional, as Pugh and Cassidy create a bond between Lib and Anna that resembles the love of a mother and daughter. 

In its shocking resolution, “The Wonder” lays no charges against those who, in its words, “supervised the starvation of one more Irish child,” and only refers to the dangers delusions of immortality and martyrdom pose to innocent victims. The narrator addresses the audience: “It is a whole sorrowful world that’s too hungry to see the wonder in every ordinary child.”

Perhaps not for the casual viewer, “The Wonder” finds its audience in those who see beyond its fable and acknowledge its poetry. The epilogue calls back to the thaumatrope — the caged and uncaged bird — this time the apparition of the narrator accompanying her voice. “In. Out. In. Out.” 

Daily Arts Writer Maya Ruder can be reached at mayarud@umich.edu.