Playwrights and screenwriters have had several years to mine the clergy sexual-abuse scandal, but it is only with John Patrick Shanley’s Pulitzer Prize–winning play Doubt that someone has written something of lasting artistic value. Doubt, which recently opened on Broadway at the Walter Kerr Theater after an extended run at the Manhattan Theatre Club, is gripping. Its actors turn in riveting performances; and the play remains remarkably balanced, scrupulously avoiding caricature and moral posturing.

Shanley, who won an Oscar for his screenplay for Moonstruck, has cleverly wrapped the sexual-abuse crisis in the cloak of a whodunit, and set the story in 1964, at a Bronx parochial school run by the Sisters of Charity. Sr. Aloysius (Cherry Jones) is the tough-as-nails principal, whose suspicions about the character of Fr. Flynn (Brían F. O’Byrne) are confirmed when one of her young teachers, Sr. James (Heather Goldenhersh), reports that a student has been removed from her class by Flynn and returned with the smell of alcohol on his breath. Complicating the problem, the boy in question, Donald Muller, whom we never meet, is the only black student in the school.

Setting the play in the 1960s provides insights into the milieu in which clergy sexual abuse might occur-a time when deference to clerical authority was more prevalent than it is today. Shanley’s choice of 1964, in the middle of the Second Vatican Council—when understanding of the roles of clergy, women religious, and laity was shifting—also offers occasions for dramatic reversals and complexity. Flynn’s gruff charm—straight out of Irish-Catholic lore—and his easy, teasing way with boys, make clear how he might use his charisma to gain the confidence of potential victims. It is one of the play’s shrewder ironies that Flynn is a proponent of the reforms of Vatican II. He regularly articulates liberal-Catholic principles—and seems to mean them. Part of the play’s genius is in drawing Flynn in such sharp contrast to Sr. Aloysius, whose Catholicism is so preconciliar that she disapproves of students’ singing “Frosty the Snowman” because it’s “heretical” and “espouses a belief in magic.” A lesser playwright would have freighted the Flynn character with all the negative and authoritarian characteristics associated with the preconciliar church, and presented Sr. Aloysius as a syrupy, saintly defender of the helpless.

Sr. Aloysius is anything but sweet. Anyone who attended Catholic schools staffed by women religious will recognize the sternly rigid yet secretly caring sister, channeled by Cherry Jones’s masterly performance. Sr. Aloysius is a tough, self-assured woman who expects a toughness from her staff and fellow nuns in all matters, great and small. She admonishes Sr. James for allowing students to write with ball-point pens—“When they press down they write like monkeys”—and cautions her against being too trusting of priests, too anxious to please: “If you forget yourself and study others, you will not be fooled.”

Armed with this steely resolve, Sr. Aloysius goes about the business of studying Fr. Flynn. After hearing from a fellow sister that the priest has been taking boys to the rectory for private talks about “how to be a man,” she invites him to her office under the pretense of an administrative meeting, coaxing a reticent Sr. James to attend as a witness. To watch Aloysius and Flynn go through the motions of courtesy (while knowing what’s boiling under the surface) is to experience an inspired moment of dramatic irony.

O’Byrne’s physical performance in this scene is enormously effective. He strides into Aloysius’s office and promptly takes her seat at the desk, making the power relationship perfectly clear. They make small talk. Aloysius offhandedly mentions an elderly sister who recently “fell on a piece of wood, and practically killed herself.”

FLYNN: Her sight isn’t good, is it?

ALOYSIUS: Her sight is fine. Nuns fall, you know.

FLYNN: No, I didn’t know that.

ALOYSIUS: It’s the habit. It catches us more often than not. What with our being in black and white, and so prone to falling, we are more like dominoes than anything else.

This back-and-forth, like so much of the play’s dialogue, is intensified by tiny dramatic movements, even covert ones, because this exchange has a comedic bent. But they reveal something important about the characters: the hint of predatory menace in Flynn’s pointed inquiry about the other nun’s health (Is she fit for work at the school?), and Aloysius’s protective nature—not naive, but smart enough to play to Flynn’s latent misogyny by comparing nuns to falling dominoes. She has his number.

The conversation stalls once Aloysius asks Flynn why he took Donald Muller out of class. Flynn explains that he removed Donald to talk to him about having drunk the altar wine, but then recognizes the meeting is a set-up, and storms out. At a loss about how to pursue her investigation, Aloysius takes a risk by summoning Donald’s mother (Adriane Lenox) to her office, but makes no headway with her either. After at first denying that Flynn has molested Donald, Mrs. Muller finally acknowledges that the abuse has taken place. But she refuses to take action against Flynn, or even remove Donald from the school, because, she explains, the priest is “the only one who pays him any attention.”

Aloysius pleads with Mrs. Muller to expose Flynn, to remove Donald from his reach, pushing finally to one of the play’s most powerful reversals, in which Muller offers an admonishment of her own: “You may think you’re doing good, Sister, but the world’s a hard place.” Adriane Lenox’s performance is compact, tragic, and utterly convincing. This wrenching scene is just one example of how Doubt turns every dramatic commonplace on its head. Even when you expect the parent of a victim to be the most scandalized, Shanley pulls the rug out from under you.

The tense last scene is a final confrontation between Flynn and Aloysius, where it’s revealed that Aloysius herself has feet of clay. Flynn is at his manipulative best. Even at this point in the play, the audience can’t be certain of his guilt or innocence. But Aloysius is. She threatens to expose him if he doesn’t immediately request a transfer. He refuses, continuing his denials.

By now, all pretense to courtesy is gone. As the conversation escalates, Aloysius makes no effort to hide her disdain for Flynn, but he will not yield. The actors never succumb to the temptation to overplay the intensity of the scene, yet they clearly convey what’s at stake for Flynn and for Aloysius—his future as a cleric and her moral integrity. In the end, however, neither Flynn nor Aloysius walk away unscathed.

“In the pursuit of wrongdoing, one steps away from God,” Aloysius tells Sr. James. This pillar of strength, a woman certain of herself, her convictions, her church, is broken by exposing what she’s convinced is a horrific injustice. The price she pays is her certainty. “Oh, Sr. James,” she sighs in the play’s final sorrowful line, “I have such doubts.”

The doubt in the title refers to multiple questions and betrayals. Like other Catholics confronted with clergy abuse, Sr. Aloysius comes to question and have doubts about herself. For in prosecuting the injustice she perceives, she’s driven to betray her own moral code. Even in the rooting out of something as abominable as pedophilia, the play shows, other moral truths can be lost. That’s the ambivalence so compellingly presented here.

Did Flynn do it? The play itself doesn’t say. By not resolving the case, Doubt shows that its ambition extends beyond the whodunit genre. It’s gutsy for Shanley to withhold the emotional satisfaction of closure in a drama fueled by such a fraught subject. And in doing so, Doubt reflects what the sexual-abuse crisis has been for so many Catholics: an occasion of profound grief for a church they, like Sr. Aloysius, believed in.