Like many of the best plays New York has seen lately – and “Doubt” is certainly one of those – John Patrick Shanley’s story has qualities barely hinted at by a plain description. A nun suspects that a priest may have interfered with one of the students: Considering the trouble the Catholic Church has had lately, this sounds like the work of a playwright who’s spent too much time watching CNN.

As it reopens on Broadway, it’s clear there’s much, much more going on in “Doubt.” Just as Richard Greenberg’s “Take Me Out” concerned vastly more than a gay baseball player, and Lisa Loomer’s “Living Out” had something to say about American society in general and not just lawyers and nannies, Mr. Shanley’s plot captures a moral and philosophical universe.

It’s 1964, and Father Flynn (Brian O’Byrne) is the popular new priest at St. Anthony’s School in the Bronx. But Sister James (Heather Goldenhersh) thinks something improper may be happening between him and one of the boys, the first black student in the school. She takes her suspicions to the principal, the supremely old-school Sister Aloysius (Cherry Jones).The administrator does not have proof, but she has her certainty. The story of her prosecution of Father Flynn touches on questions of justice, compassion, moral responsibility, the true meaning of Christ, sex, power, race – and, naturally, doubt.

Before getting all caught up in the exquisite writing, the main thing to say about “Doubt” is that it’s the most exciting show in town. No gunshots, no skin showing, no easy thrills. Still Mr. Shanley, director Doug Hughes, and a brilliant cast make this a riveting 90 minutes. It has been just four months since the play opened off-Broadway at the Manhattan Theatre Club. Many of the lines, scenes, and tableaux left marks on my memory. It made no difference: Seeing the play again this week, as the wily Father Flynn tried to out duel the overbearing Sister Aloysius, I was still enthralled.

Partly this is due to the compactness of Mr. Shanley’s writing. The script is taut, but every scene resonates. He has found a way to let little details of character signal large thematic concerns. Sister Aloysius lures Father Flynn to her office on the pretext of talking about the Christmas pageant. We see again how conservative, in taste and temperament, she is. Father Flynn, who favors including pop songs in the pageant, is younger and more liberal. Sister James, stuck in the middle as usual, agrees with Father Flynn but doesn’t want to say much for fear of incurring her superior’s wrath.

As we laugh at all these insights into the characters’ personalities (this is a very funny play when it wants to be), Mr. Shanley is quietly airing a debate about the reforms enacted by the Second Vatican Council. A dense argument over dogma is smuggled into the play under the guise of disagreeing about whether “Frosty the Snowman,” as Sister Aloysius maintains, “espouses a pagan belief in magic.”

Ms. Jones, always a formidable actress, is positively colossal here. In her glasses, habit, and black bonnet, she is the picture of severe vigilance. You may have misgivings about Sister Aloysius’s beliefs, but she doesn’t.

“The children should think you see right through them,” she scolds Sister James.

“Wouldn’t that be a little frightening?”

“Only to the ones that are up to no good.”

From a lesser actress, a performance so single-minded would seem flat. Ms. Jones finds every little tone in Sister Aloysius’s determination to break Father Flynn. To enumerate the admirable things she does here would be to make a list of what the very finest acting ought to be: settled, immediate, richly voiced, generous to castmates, resistant to cheap laughs. It is a performance to savor.

Such compact writing requires acting of great refinement and directing as exquisite as Mr. Hughes’s. As in its Off-Broadway run, Mr. Shanley dedicates the play to Catholic nuns like Sister Aloysius and Sister James. A nun used to teach music at the school, we learn, but now it is taught by a lay person. “Not enough sisters,” Ms. Jones says. A few words tell us all we need to know about the twilight that’s settling over their way of life.

The talented young Ms. Goldenhersh manages to distinguish herself next to this galvanic performance: no easy feat. She is sensitive and affecting. Adriane Lenox, who turns up late in the show playing the boy’s mother, also holds her own. Her scene with Ms. Jones plays better now than it did Off-Broadway, though it remains the one sequence in the play that isn’t completely successful.

As Ms. Jones’s antagonist (or is she his?), the gifted Mr. O’Byrne makes another addition to his list of walking enigmas. Having played a serial-killing pedophile who was a softie at heart in “Frozen,” here he manages to alternate between warmth and high-handedness, real affection and what looks like the most cynical calculation. The night I saw the show, Mr. O’Byrne still seemed to be finding his range in the Walter Kerr: The performance was a little hot, a little noisier than it was Off-Broadway, or needs to be here.

But it’s Mr. O’Byrne, more than anyone else, who lashes the audience to the play. “What do you do when you’re not sure?” he says at the very top of the show. He is addressing us in his radiant green and gold robes. He is the priest, we are his congregation, and as such he compels our attention. He tells Sister James at one point that he makes up the stories he tells in his sermons, “in the tradition of the parable.” “The truth makes for a bad sermon. It tends to be confusing and have no clear conclusion,” he tells the young nun.

So it’s significant that Mr. Shanley has given this play the subtitle “A Parable.” As Ms. Jones and Mr. O’Byrne battle every night over the truth of what happened, and for our sympathy, it’s up to each audience member to decide which lesson he wants to impart. The opportunity to do so again – on Broadway, no less – is reason to give thanks and praise.

(219 W. 48th Street, 212-239-6200).