Probably not. But the past they summon — a time when, as one of them puts it, they existed at the very “bull’s-eye of life” without knowing it — almost blinds in its radiance before being swallowed by night. There’s nothing like regret and Gaelic retrospect to find the poetry in the prose of the everyday.

That, more or less, describes the ravishing first third of Sebastian Barry’s “On Blueberry Hill,” the seriously unbalanced new play about love, hatred and redemption that opened Sunday night at 59E59 Theaters as part of Origin’s 1st Irish Festival. It is a common point of view in Irish literature, this transformation of nostalgia into a sacred elegy.

But Barry, whose works include the acclaimed novels “The Secret Scripture” (2005) and “Days Without End” (2016) and the excellent play “The Steward of Christendom” (1995), has an uncommon gift for finding hypnotic music in this perspective. And when his language is delivered by consummate Irish actors like Niall Buggy and David Ganly, the entire cast of “On Blueberry Hill,” it’s hard not to sink into a state of contented sadness that you half wish would go on forever.

What’s being described in those opening monologues is nothing more than the events of ordinary childhood and family life — trips to the seaside, the taste of cold soda on a hot day, dancing to the Fats Domino song that gives the play its title and that feeling beyond words known as love. Yet these are steeped in a luminous wonder that makes you want to weep for what you take for granted in your daily existence.

Life, however, is not just a sustained stream of sweet, solemn reverie, and neither is Barry’s play, a Fishamble production directed with a slow, caressing hand by Jim Culleton.And at a certain point in this 100-minute production, the plot that brings its two characters into convergence takes over with increasing, strong-armed clumsiness.

Ganly portrays PJ, a priest, and Buggy is Christy, a construction worker. They are the occupants of the outsize bunk bed at the center of Sabine Dargent’s set, shrouded in Stygian shadows by Mark Galione’s lighting. (Denis Clohessy provided the subliminal, otherworldly sound.) To reveal how they came to live in such proximity would be to spoil the surprises of a play built as a series of staggered revelations.

Let’s just say that each has been brought to this place — which we eventually learn is a prison cell — by acts of violence. The particulars of those acts remain tantalizingly mysterious, even after they have been described in (changing) detail.

In PJ’s case, especially, it’s the ambiguity of what happened to him one fine day on the island of Inishmore that feels so resonant and, paradoxically, so illuminating. At that time a fledgling priest, on a day’s holiday with a younger seminarian, PJ finds himself, irrationally and inexorably, propelled by an urge that he has never been able to explain.

He describes it as “a strange little instinct like something from childhood, a sudden capricious wickedness, a piece of wretched devilment.” It is a feeling that, before he knows it, has led to another person’s death.

PJ may remain incapable of defining what possessed him that day. But Barry has slyly provided enough information for you to intuit the social, sexual and spiritual influences that have coalesced here to create this horrific moment. As Ganly delivers his account of it, with a stunned and eternal woundedness, questions of culpability become moot, and you feel a bottomless pity.

What PJ did that day sets off a chain of events that causes Christy, an older man, to commit an even more heinous crime. This one, too, is recalled with a surreal, dreamlike fogginess.

Yet despite the perplexed anguish Buggy brings to the telling, it is here that you start to feel detached from the narrative. And be warned: Your credibility will be ever more strained before the play ends.

By then, you’re likely to be feeling sentimental about the delicacy of the work that you thought “On Blueberry Hill” was going to be. Perhaps you’ll even identify with its reminiscing characters, or with the way they were, when this play seemed so full of gentle promises.

—

Production Notes:

‘On Blueberry Hill’

Through Feb. 3 at 59E59 Theaters, Manhattan; 646-892-7999, 59e59.org. Running time: 1 hour, 40 minutes.

By Sebastian Barry; directed by Jim Culleton; sets and costumes by Sabine Dargent; lighting by Mark Galione; sound by Denis Clohessy; production managers, Marie Tierney and Joe Glasgow; stage manager, Miriam Hyfler; dramaturge, Gavin Kostick; production coordinator, Ronan Carey. Presented by Fishamble: The New Play Company.

Cast: Niall Buggy (Christy), David Ganly (PJ) and Ronan Collins (voice, as himself).

This article originally appeared in The New York Times.