Halfway through “Detroit,” Lisa D’Amour’s funny, dark and timely new play with a pitch-perfect cast that includes David Schwimmer and Amy Ryan, a character named Sharon explains that she has just had a run-in with a neighbor, who accused Sharon’s dog of crapping all over her lawn.

“But we don’t have a dog,” Sharon’s husband Kenny says.

“We don’t have a dog. Exactly,” Sharon says. “I said ‘Ma’am, people have accused me of many things before, but they never accused me of having a dog.’”

It’s a surreal moment, never explained, in a play that until then has been deeply rooted in present-day reality – the reality facing those struggling to stay in the middle class. Call them the 47 percent.

Kenny and Sharon (Darren Pettie and Sarah Sokolovic) are new to the neighborhood, a once-bright, friendly suburb of what may or may not be Detroit. The title is more of a metaphor, and it is one of several, a symbolism expertly and unobtrusively threaded throughout the work.

We first see the couple in the backyard of their next-door neighbors Ben and Mary (David Schwimmer and Amy Ryan), who invited them to share a barbecue. Ben has just been laid off from his job as a banker. He plans to set up a website that will launch a new business as a financial adviser for those facing a credit crisis. His wife Mary supports the two of them as a paralegal. They are, as it turns out, in better shape than their new neighbors. Both Kenny and Sharon are employed, but they work at low-paying jobs with little security, he in a warehouse, she at a call center. Worse, they met in drug rehab, and it’s not clear that the rehab completely worked.

Indeed, nothing quite works the way it should for the characters in “Detroit,” from the patio umbrella in Ben and Mary’s backyard to their physical well-being right up to each character’s literal dreams and lofty plans.

“I’m supposed to set goals and take night classes that will expand my horizons,” Sharon confides in Mary. “But to be honest I feel like the real opportunities are the ones that fall into your lap. Like winning the lottery or somebody’s rich Uncle needing a personal assistant.” Kenny and Sharon seem to be placing their hopes in a personal lottery, counting on winning what sounds like a dubious lawsuit against a supermarket where Kenny slipped and fell a few years back — if in fact Kenny is telling the truth.

“Detroit” seems composed of casual conversations and everyday scenes between the two couples as their friendship deepens. But there is more going on here, as the explosive climax and aftermath make startlingly apparent; the play turns from orienting naturalism to an unnerving surrealism, each of the characters delusional in their own way. But the tensions are hinted at all along, thanks to director Anne Kauffman, who has assembled a production at Playwrights Horizons that does justice to D’Amour’s play, which was a finalist for the Pulitzer Prize for Drama and was at one time planned for Broadway. The acting is spot-on, each of the performers capturing the dual nature of their characters. Amy Ryan’s Mary is polite and well-meaning, and also fearful, awkward and a secret drunk. David Schwimmer’s Ben is amiable and assured, but secretly clueless and drifting. Pettie’s Kenny — like his wife a mysterious character both to the other couple and to the audience — is one hell of a guy, but also a dangerous, resentful menace. Sarah Sokolovic’s Sharon is cheerful and friendly, but also harbors a feeling of hopelessness. The always reliable John Collum makes a late appearance in the play, primarily to provide some necessary exposition and a dollop of symbolism, but, thanks to his delivery, he has the funniest, most poignant line in the play (which I won’t spoil.)

Adding to the effect are Louisa Thompson’s sets, which rotate between the two houses, front and back, of the two couples, and Matt Tierney’s sound design, which, with its combination of cricket chirpings and revving engines, offers its own lesson in suburbia. Everything about the production, in other words, works well to show some ways in which America is not working.

Detroit

At Playwrights Horizons

By Lisa D’Amour

Directed by Anne Kauffman; sets by Louisa Thompson; costumes by Kaye Voyce; lighting by Mark Barton; sound by Matt Tierney; Cast: John Cullum (Frank), Darren Pettie (Kenny), Amy Ryan (Mary), David Schwimmer (Ben) and Sarah Sokolovic (Sharon).Running time: 1 hour 40 minutes with no intermission.

Detroit ran through October 28, 2012.