Grunt Casting: New World?s soldiers have a private moment.

Possibilities—grand ones, and gruesome, too—are what drive the rousing pop chorale that opens Jason Robert Brown’s Songs for a New World: “A new world calls for me to follow/A new world waits for my reply,” the lyric goes, over an irresistible melody that’ll arc its way over at least three upward modulations—and return whenever Brown wants to toy with the audience’s sense of anticipation.

So let’s start by applauding the scope of Suzanne Richard’s sense of the possible and the eloquence of her reply to the ideas Brown’s ingratiating little character-sketch tunes have sparked. With one added song and a few lyric tweaks, her ambitious rethink of what was originally a four-performer song cycle blows the show up in more than one way, inflating the cast to a stage-filling 24 and grafting on a loose America-at-war plot—complete with a smarmy politico, his disillusioned wife, a gaggle of angry anti-establishment protesters, and a whole platoon of soldiers stationed in the Iraqi desert. Not all of the last, as you might imagine, will survive the second act; the good news is that Richard’s staging comes at that inevitability with a restraint and an attention to character that steer the show away from exploitation and toward something genuinely moving.

Not that the Open Circle Theatre’s production is revelatory, exactly. The relationships between the singers who step forward to sell those tunes—whose charms range from the honky-tonk piano of “The River Won’t Flow” to the cabaret sophistication of the show’s calling-card number, “Stars and the Moon”—aren’t always as clear onstage as they are in the program note that explains how Lanny Slusher’s calculating Politician and Warren Snipe’s strapping, camo-clad African-American Soldier are connected. (They’re meant to be dad and adopted son.) And there’s something a little suspect about trying to marry the worldly disappointments of “Stars and the Moon” and the shallow bitternesses of “Just One Step” within a single aggrieved-wife character, lyrical emendations or no.

But the expanded forces add a shivery power to the best of Brown’s songs, especially that insanely catchy opening anthem, and there’s something generously big-picture about the way Richard has opened out a show that’s essentially a string of intimate moments. The blissfully maternal “Christmas Lullaby,” delivered in this production by a blood-soaked female medic (Debra Buonaccorsi) in a desert-base chapel, becomes an aching plea for strength rather than a mere placid statement of faith, and there’s a sharp rage to “King of the World,” now sung by a paraplegic protester (Rob McQuay) who’s been arrested at a rally and thrown into a cell without his wheelchair; his blazing reading of the song is one of the night’s solo high points.

Which points up, yet again, the payoffs of Open Circle’s restless experimentation. The company makes a point of integrating actors with various disabilities, using what some might describe as limitations to spark new ideas about how to tell stories. So Snipe performs “Flying Home,” for instance, in the stirringly lyrical gestures of singing sign, while James Garland sings the melancholy melody in a ringing tenor, and “She Cries,” once just a snarky number about a guy’s manipulative girlfriend, becomes a full-on comedy routine with three men, including a wise-ass sign-speaking bodyguard, trading dating horror stories.

Another example, and a fun one, is the stage chitchat that goes on between background characters: In most shows, the actors get to invent it, and they don’t usually have to worry about what they’re saying. The neat reversal this production offers is that some of that upstage mumbling is being done in sign, which means that the actors have to keep it both relevant and clean—and that the ASL-speakers in the house have an advantage. Me, I’m dying to know what I missed.

One thing not to miss: Watch, when Brown assembles a series of expansive chords at the end of a big number, how sign master Monique Holt and choreographers Shula Strassfeld and Peter DiMuro stagger and stack the ensemble’s gestures in a visual echo of the music’s build—it’s thrilling, and it makes you think about how many channels of communication we take for granted, and how many we usually overlook. Turns out a show driven by the idea of possibilities—of openings to new worlds—was a very fine choice indeed.