Emma Donoghue is not a novelist for the claustrophobic. The type of setting that she made her signature in “Room” — her award-winning 2010 novel about a mother and son held captive together in a small room for years — is the one she returns to in her exquisite new novel, “The Wonder.” Day after day, an 11-year-old girl and her nurse are confined to a cramped bedroom, barely “three paces each way.” To make matters even more oppressive, the girl has refused food for weeks; in a real sense, she’s shrinking into nothingness.

"The Wonder" by Emma Donoghue (Little, Brown)

These rooms of Donoghue’s may be tiny and sealed off, yet they teem with life-and-death drama and great moral questions. Hesitant readers may think that they’d rather lose themselves in stories with a larger sweep, a little more air; but Donoghue does so many intricate things within these small spaces of hers that, for a time, they become the most compelling places to linger. What was it that the poet William Blake said about seeing “a World in a Grain of Sand . . . ?” Something of that kind of mystic expansion happens in Donoghue’s rooms.

Unlike her characters in “Room,” the girl and woman in “The Wonder” have chosen to enter their shared cell: They’re led in, respectively, by faith and duty. The story takes place in the early 1860s, in a boggy town in central Ireland called Athlone. An otherwise ordinary young girl named Anna O’Donnell has transformed herself into what the locals are calling “the living marvel.” It seems she’s “a magical girl who lives on air.” For the past four months, Anna apparently has swallowed nothing more than a few teaspoons of water, yet she seems unchanged. Skeptics jokingly speculate that Anna may be living on scent; the local doctor has done some research and found a theory that some women can live without food by subsisting on reabsorbed menses. When pressed, the pious Anna eventually confesses that she’s surviving on manna from heaven.

A committee of prominent men in the village (including the aforementioned doctor and the town’s Catholic priest) hires two nurses to keep a round-the-clock watch on Anna for two weeks, to document a miracle or discover a fraud. One of the nurses is a tight-lipped nun; the other is a widowed Englishwoman named Elizabeth “Lib” Wright. Lib is “a Nightingale” — a veteran of the nursing brigade that Florence Nightingale assembled at Scutari during the Crimean War. Since the conflict ended, Lib has been working, unhappily, as a private-duty nurse and, most recently, in a hospital where she is treated as little more than a servant. Because she yearns for “a less narrow life,” Lib eagerly accepts the assignment in Ireland, although she doesn’t know until she arrives any specifics about her new patient’s condition.

What ensues is a tight, intense drama involving a contest of wills and a clash of worldviews within Anna’s tiny bedroom. Lib tries to alternately command and cajole her patient into eating, to no avail. Anna attempts to cozy up to this exotic English nurse and is curtly rebuffed. Throughout her eight-hour shifts, Lib, who feels as though she were “being paid just to stare,” tries to figure out exactly what she’s staring at: By turns, she regards Anna as “a false little beggar,” a victim of her parents’ and the town’s desires for fame, and a propaganda — and perhaps even a fundraising — tool for the Catholic Church. Sporadically, these fierce wrestlings are interrupted by brief visits from Anna’s parents, or pilgrims seeking to touch Anna, or an investigative journalist from the Irish Times. But chiefly, Lib and Anna sit together in that room:

Emma Donoghue (Nina Subin)

“Now there really was nothing left to do. Lib took the second chair. It was so close to Anna’s that their skirts were almost touching, but there was nowhere else to place it. She considered the long hours ahead with a sense of awkwardness. She’d spent months on end with other private patients, but this was different, because she was eyeing this child like a bird of prey, and Anna knew it.”

There are strains in this increasingly sinister situation of both Henry James’s “The Turn of the Screw” (the isolation of a somewhat troubled caregiver with her mysterious young charge) and Ron Hansen’s brilliant 1991 novel about female martyrdom, “Mariette in Ecstasy.” Anna begins to weaken dramatically shortly after Lib’s arrival: Her hair falls out in clumps, her skin flakes, her swelling worsens. Lib must ask herself whether her own near-constant surveillance (relieved only when the nursing nun arrives for her shift) is somehow responsible for the girl’s decline. Lib also mulls over metaphysical questions, particularly wondering about the existence of a God who would allow the suffering she sees before her, as well as the torment she witnessed at Scutari. All these ruminations take place against the soundtrack of Anna’s near-constant murmured prayers.

Donoghue manages to engage these larger mysteries of faith, doubt and evil without sacrificing the lyricism of her language or the suspense of her story line. Anna may or may not be a genuine “living marvel,” but “The Wonder” certainly is.

Maureen Corrigan, who is the book critic for the NPR program “Fresh Air,” teaches literature at Georgetown University.

the wonder

By Emma Donoghue

Little, Brown. 304 pp. $27.