Diversionary Theatre's 'Hour of Great Mercy' finds a quiet grace amid tragedy in Alaska

And you thought global warming was enough of a worry: Near the start of Miranda Rose Hall’s big-hearted new play “The Hour of Great Mercy,” a folksy radio host named Roger has a meltdown so fiery it threatens to liquefy half of Alaska.

The episode — the result of an unexpected on-air meeting between Roger (Tom Stephenson) and his long-estranged brother, Ed (Andrew Oswald) — is by turns funny, poignant and more than a little shocking, as Roger descends into insults and slurs.

But that complex mix of tones is an abiding quality of Hall’s writing in “Mercy,” which just opened a worthy world-premiere staging under Rosina Reynolds’ finely tuned direction at Diversionary Theatre.

Diversionary may have captured lightning (or, more aptly, the northern lights) in a bottle by landing the first production of this Alaska-set piece from Hall, an on-the-rise writer who had a high-profile professional debut just last fall at Lincoln Center Theatre in New York.

The new work by this protegé of the much-admired playwright Sarah Ruhl plumbs some weighty emotional depths in its story of a Jesuit priest (Ed) who returns to family roots in the tiny, icy town of Bethlehem, hoping to mend ties or at least receive (and extend) some measure of forgiveness over past tragedy.

(Read our preview story on “The Hour of Great Mercy”)

To reveal too much about what happened five years earlier — and what’s happening to Ed now — would do a disservice to the play. But suffice to say the schism between him and his brother goes far beyond bitterness, and is compounded by Roger’s apparent antipathy toward Ed’s gay identity.

The characters in “Mercy” — including Roger’s kind but exasperated wife, Maggie (Dana Case), their neighbor and lovable local gadfly Irma (Eileen Rivera), and Ed’s gentle newfound soul mate Joseph (Patrick Mayuyu) — are compelling enough that they could bear even more fleshing out.

That’s true, too, of the play, which unfolds in two relatively short halves with one intermission. Things escalate quickly in this saga, whether we’re talking arguments, love affairs or challenges to mortality, and it feels as though the narrative should be given a bit more time and space to breathe.

But one thing Hall does beautifully is to radiate a sense of wonder at, and acceptance of, uncertainty and flux — whether that has to do with nature, human behavior or religion.

The latter is a key presence in “Mercy,” which is named for the time of day (3 p.m.) that, in Catholic tradition, Christ is said to have died on the cross. And one of Ed’s most thoughtful philosophies — one that has put him odds with his church — is that “there’s nothing on Earth more queer than God — so fluid, so encompassing the spectrum, and so devoted to radical love.”

Huge questions reside comfortably alongside the amusingly prosaic: Joseph, a nurse whom Mayuyu plays with appealing wit and kindness, at one point laments the irony that despite Alaska’s vastness, everyone knows everyone else’s business in this little town.

That includes the outspoken Irma, whom Rivera plays with show-stealing comic chops. Stephenson skillfully gets at layer upon layer of pain in the struggling Roger, who can’t seem to move beyond loss, while Case lends the long-suffering Maggie a stark feel of patience worn to the bone.

And in Oswald, an actor with a natural affinity for gentle dignity, director Reynolds has found an ideal Ed, whose own struggles can’t extinguish the light within.

There are lights without, too: The Aurora Borealis, witnessed in awe by Ed and Joseph in a romantic scene that combines the best of Kristen E. Flores’ elegantly elemental set, Curtis Mueller’s lighting and Emily Jankowski’s sometimes haunting sound design. (Elisa Benzoni’s understated costumes also work well.)

The moment can make quiet contemplation feel like a hymn.

When: 7 p.m. Thursdays; 8 p.m. Fridays-Saturdays; 2 p.m. Sundays. Through March 3.

Where: Diversionary Theatre, 4545 Park Blvd., University Heights