Smack dab in the middle of the theater district, there’s a don’t-miss story of a green girl who weathers prejudice and false friends. It’s played by a crackerjack company and features some heart-wrenching songs.

No, it’s not “Wicked.” But if commercial success and awards were justly bestowed, the Phoenix Theatre Ensemble’s “Wolfpit” would be just as crowded as its very big sister across the street. “Wolfpit” may not be theater for a popcorn-crunching teenybopper. But Glyn Maxwell’s 1996 play can guarantee more mental and linguistic acrobatics than any flying monkey.

The Phoenix Ensemble – the group that rose from the ashes of a contentious battle at the Cocteau Rep – has scored a coup in making Mr. Maxwell its resident playwright. Nowhere else in New York do you find a writer with new work so dense and lyrical; nowhere at all do you find verse drama in such good hands.

Mr. Maxwell, a noted poet (in an age when poets are almost never noted), has only had a few of his plays mounted in New York. But literary managers tend to keep their eyes open for the next David Mamet, or the next Richard Greenberg. How many of them know to keep their eyes peeled for the next Christopher Fry?

Mr. Maxwell tends to springboard off original sources, rather than generating his plots from scratch. Last year’s “The Forever Waltz” riffed on the Orpheus myth, and “Wolfpit” is based on two 12th-century accounts of weird goings-on in Suffolk. Tending the fields one day near a wolfpit (essentially, an overgrown ditch), some reapers came across a brother and sister, each green from head to toe, and “clad in raiment of unknown material.” They spoke no English, and refused all food except green beans, yet the townsfolk took them in.

Mr. Maxwell takes this meager outline, including some startlingly mystical things the children say about their homeland, and turns it into a gorgeous, earthy, romantic meditation on change and fellow feeling. But don’t be thrown by the fairy-tale setup. Mr. Maxwell sees his characters with clear, damning eyes. In this patch of England, there are more wolves out of the pit than in.

Tom Parch (Craig Smith) would rather laze the day away than work, so when the two eldritch children appear on his patch of hay, he’s eager to take a break. As Mr. Smith plays him, Tom is a dangerous buffoon: Though his sloth makes him a butt of jokes, his jolly belly and beard hide a completely amoral mind. Chittering in some otherworldly tongue, the Green Girl (Nicole Raphael) and her brother (played convincingly in drag by Margo Passalaqua) immediately attract the village’s attention. But Tom Parch must only wait to make his profit on them.

Sara Staner (Elise Stone), wife to the numbskull Ned (Jonathan Tindle), realizes she can gain favor by cozying up to the children. Infatuated with Master Richard Calne (Jason O’Connell), the lord of their little fief, Sara follows the changelings into his manor house, where she tries to teach them to speak. But as the girl learns English, she also begins to fade – first to leaf-green, then to gold. And a gold girl catches the master’s eye. Horribly, everyone who once helped the Green Girl now wants to either sleep with her or eliminate her as a rival – and Tom Parch finds it easy to turn from reaper into raper and from raper into pimp.

Cramped onto the tiny Theater Three stage, the company nonetheless creates a convincingly menacing world. Robert Klingelhoefer’s set looks like a giant crop circle, with a floor that looks like beaten-down wheat. Everything, even the backdrop, is woven; the whole play could be taking place inside a Wicker Man – another image of medieval mysteries gone terribly wrong. Best of all, at the start of each act, the company sings a song heralding a new season – and even in spring they sound hardy and cruel.

Robert Hupp keeps his company moving briskly, letting the tide of Mr. Maxwell’s poetry dictate the pace. All the actors are well-spoken, but even those who overplay (like the unaccountably plummy Ms. Stone), are goosed along by Mr. Maxwell’s galloping verse.

Occasionally, a company and a playwright will meet and match, and the Phoenix has found its collective muse. Its entire game seems heightened, here – it’s almost as though Mr. Maxwell was writing with some of these actors in mind. Don’t be fooled into thinking this model is old-fashioned. It might be the Dark Ages onstage, but the company has found a path into the spotlight.

Until May 6 (311 W. 43rd Street, third floor, 212-352-3101).