Bruce Norris has been acting in New York and writing in Chicago for almost a decade now. Nothing against Mr. Norris’s acting — he has dependably demonstrated his skill as a character actor — but judging from “The Pain and the Itch,” this city has been getting the short end of the stick.

The play is a bruising dissection of modern liberalism’s unchecked prejudices. It begins as a distressing look at misplaced parental anxieties and, through the artful guidance of director Anna D. Shapiro, evolves into a chilling commentary on the prospect of global harmony. It is also, I should mention, the funniest new play to reach New York in a long while.

The setup — dysfunctional family gathering for the holidays — gives little indication of the incisive devilry to come. Clay and Kelly (Christopher Evan Welch and Mia Barron) have invited Clay’s immediate family to their suburban home for dinner. He can barely stand his brother, a smug plastic surgeon named Cash (Reg Rogers), never mind Cash’s barely legal Russian bigot of a girlfriend, Kalina (Aya Cash). Not even his mother, placid Carol (the irresistible Jayne Houdyshell), can keep the peace for long.

The family pauses between scorching confrontations just long enough to deliver their profoundly unsurprising opinions on the following topics: Starbucks (bad), the Dalai Lama (good, although theological details remain fuzzy), George W. Bush (very bad), Charlie Rose and Bill Moyers (both very good), and blacks and Mexicans (good as long as they don’t talk during movies, except as far as Kalina is concerned). When conversation flags, there’s also the issue of an itchy (and highly suspect) rash on the genitals of Clay and Kelly’s 4-year-old daughter, Kayla.

(This last plot point, not to mention the general level of unpleasant conversation transpiring onstage within earshot of the young actress playing Kayla, generated a fair bit of audience and media tongue-clucking during the play’s acclaimed Chicago run last year.)

But while the family’s ideological stance is apparent, “The Pain and the Itch” keeps a few key pieces of information tucked away. For one thing, who is the polite Muslim to whom Clay and Kelly unburden themselves in the living room periodically? Why is he weeping? What does he want from this family? Or do they want something from him? And why is he so curious about the value of both their dining room table and Clay’s shoes?

Mr. Hadid (Peter Jay Fernandez), it turns out, is a cab driver who has suffered a great loss. His life has clearly intertwined with the family’s, crossing racial and socioeconomic lines in potentially surprising ways, and Mr. Norris frequently halts his telling of the fateful holiday dinner by having various family members address Mr. Hadid directly. (Ms. Shapiro, a longtime collaborator with Mr. Norris, shows particular skill in moving in and out of these extended flashbacks, aided by Donald Holder’s keen lighting.)

But “Crash” this ain’t: For all the smug holiday discussion about diversity and tolerance, the convergences between these two worlds are infrequent and unsatisfying. When Mr. Hadid can be torn away from inquiring about the worth of the family’s possessions, he patiently, gently dismantles the unexamined pieties whizzing around him.

Take this simple, seemingly innocuous cliché: “I’m doing what’s best for my family.” What parent hasn’t offered this excuse? It’s on this that Mr. Hadid goes to work:

CLAY: Basically, we’re about the family.
MR. HADID: Your family.
CLAY: No.
MR. HADID: You are not for my family
CLAY: No. I’m only talking about advantages. Giving your child every possible advantage.
MR. HADID: Advantage over my child.

Viewed through this prism, every parental action is a skirmish of social Darwinism. The central irony — and “The Pain and the Itch” is stuffed with unsparing ironies — is that Clay and Kelly are unsuccessful at almost every aspect of parenting. As they shield Kayla from the scourges of lipstick and fake swords and baby talk, they’re also bellowing the vilest dialogue. Clay can’t even keep his hardcore pornography separate from the girl’s Wiggles tape. No wonder Kayla’s dialogue is confined to timid shrieks. (Ada-Marie L. Gutierrez, who gave a direct, clear-eyed performance at a recent preview, alternates with Vivien Kells in the role of Kayla.)

The occasional wave of hysteria from Ms. Cash as the Eurotrash girlfriend notwithstanding, the cast is terrific from top to bottom. Ms. Barron’s Kelly provides the play’s brittle emotional core, while Messrs. Rogers and Welch each prove both hiss-worthy and sad in their own, elaborate ways. (Mr. Rogers even manages to deliver an Act II monologue that sums up the author’s thesis without screeching the play to a halt.) The poised Mr. Fernandez, meanwhile, skillfully nudges the action toward its memorable climax.

Best of all is Ms. Houdyshell’s Carol, retreating to her comfort zone of cultured banalities as the rest of the family slides into chaos. Ms. Houdyshell, so memorable in last year’s “Well,” plays another endearing/exasperating do-gooder here; she may not have the same range to work with this time, but she is both a spot-on caricature and a welcome respite from the surrounding savagery.

Early on in the evening, Mr. Norris delivers a blistering indictment of not-in-my-backyard hypocrisy, as Cash eviscerates everything the family appears to stand for: “See, they feel bad because what they practice doesn’t square with what they preach. … And you want to say to these people: ‘Hey, you don’t have to change what you practice. That’s way too hard. Just change what you f——-g preach.'”

With “The Pain and the Itch,” Mr. Norris has written the rare political play that’s devoid of preachiness. His voice is wicked and wise, and the sooner New York catches up with all those other plays that started out in Chicago, the better.

Until October 8 (416 W. 42nd St., between Ninth and Tenth avenues, 212-279-4200).