"The Realistic Joneses," at Yale Repertory Theater NEW HAVEN - Intimations of mortality hover in the pauses punctuating the dialogue in "The Realistic Joneses," the tender, funny, terrific new play by Will Eno at the Yale Repertory Theater here. Mr. Eno's voice, which teases out the poetry in the pedestrian and finds glinting humor in the static that infuses our faltering efforts to communicate, is as distinctive as any American playwright's today. He writes about big matters - nothing bigger than life and death, after all - as if they were incidental oddities deserving of wry comment but no great moralizing or posturing. "The Realistic Joneses," directed with grace by the busy Sam Gold, is dappled with the quirky non sequiturs and deadpan wordplay that are among Mr. Eno's signature effects, along with a quiet insistence on the majesty and mystery of human existence. As delivered by an ideal cast - Johanna Day, Glenn Fitzgerald, Tracy Letts and Parker Posey, all keenly attuned to Mr. Eno's sensibility - his off-kilter dialogue comes to seem as natural, and lovely, as the chirping of crickets and the sound of bird song. Such images spring to mind because the humming of the natural world is heard throughout "The Realistic Joneses," which is set in a small town in the countryside (more rural than Mr. Eno's "Middletown"), where two couples who share the same last name find their lives slowly twining together in ways large and small. Bob and Jennifer Jones (Mr. Letts and Ms. Day) are taking in the night air in the backyard when John and Pony Jones (Mr. Fitzgerald and Ms. Posey), perhaps a decade or so younger, come to introduce themselves, bottle of wine in silver cellophane in hand. They have just moved into a house down the road. Conversation lurches from friendly and awkward to suddenly intimate, when Jennifer confides that Bob has a disease for which he is undergoing complicated treatment. "Say no more," says Pony. Have you had experience with something like this? Jennifer naturally responds. "I just didn't want you to say any more," Pony replies flatly. And nobody does flat as funny as Ms. Posey. That's the Eno touch: the startling, often hilarious eruption of blunt honesty or, just as often, offhand profundity, into the meandering byways of everyday chitchat. In the second scene Jennifer and John run into each other at a grocery store, where they embark on another fumbling conversation. "I studied Italian in school," Jennifer says at one point, apropos of nothing. After she confesses that the strain of dealing with Bob's illness is getting to her, John suddenly takes hold of her arm. What are you doing? Jennifer asks, mildly confused. "I don't know," John says. Reaching out. "Because," he responds. And because you have pretty eyes. They're sad, but they're really pretty. They're good. "Well, that's very - I actually need glasses to read," Jennifer says, flustered. Interesting. Not really, of course, but that's the kind of meaningless remark from which Mr. Eno derives both humor and twinges of quiet feeling. And what is truly interesting about his writing is how he sidles up to seriousness so casually, tiptoeing toward the momentous by composing scenes that have the rhythms of offbeat sketch comedy with a metaphysical twist. We soon learn the reason for John's attempt to connect with Jennifer: he is suffering from the same terminal disease that Bob has. A leading specialist in the disease practices in town. Both marriages are loving but strained by the specter of encroaching illness. Jennifer, portrayed with a flinty earthiness suffused with quiet warmth by Ms. Day, is frustrated that Bob chooses to remain as ignorant as he can about the progress of his disease and options for treatment. Mr. Letts, the actor and author of the Pulitzer Prize-winning "August: Osage County," is also superb, making Bob's gruff denial moving and sympathetic. John has chosen denial for Pony, keeping her in ignorance of his diagnosis because of her skittishness about illness. Mr. Fitzgerald infuses his performance with a boyish sweetness that makes John's oddball observations and his lapses into moody philosophizing seem perfectly natural. And Ms. Posey, well known for her years as an indie-film queen, may just be the quintessential interpreter of Mr. Eno's idiosyncratic style, with her naturally sardonic demeanor and affinity for finding the humor (and the humanity) in seemingly humdrum dialogue. One of the funniest passages in the play, which is composed as a series of short scenes separated by slow blackouts, finds Pony making a rare attempt at prayer. She senses something amiss with John, and worries she will not be able to cope with whatever is coming. "This feels weird," she says, midprayer. No offense. You probably just think I'm one of so many people. You're probably like, my God, what is this even about? Maybe you're going to burn everything down anyway. I don't know your crazy mind. Getting to know one another's crazy minds is what the four characters in "The Realistic Joneses" try to do, even as they recognize that knowing their own is probably just as impossible. Looming above them all is the great mind - or absence thereof - known as the universe. Both the lighting (by Mark Barton) and the haunting sound design (by Ken Goodwin) evoke the feel of night in the countryside beautifully, when the world can feel either terrifyingly empty or animate with compassionate life. Although they are all facing the possibility of imminent and irrevocable loss - of life or love or both - the characters in "The Realistic Joneses" discuss their own pain and one another's with a blunt equanimity that may not always be realistic, but feels no less true. "I don't think anything good is going to happen to us," Bob says in the last scene, as both couples sit on the porch, contemplating the night sky. But, you know, what are you going to do. What indeed, Bob? The Realistic Joneses By Will Eno; directed by Sam Gold; sets and costumes by David Zinn; lighting by Mark Barton; sound by Ken Goodwin; projections by Paul Lieber; dramaturgy by Amy Boratko and Anne Seiwerath; stage manager, Jenna Woods. Presented by the Yale Repertory Theater, James Bundy, artistic director; Victoria Nolan, managing director. At the Yale Repertory Theater, 1129 Chapel Street, at York Street, New Haven; (203) 432-1234, yalerep.org. Through May 12. WITH: Johanna Day (Jennifer Jones), Glenn Fitzgerald (John Jones), Tracy Letts (Bob Jones) and Parker Posey (Pony Jones).