Let’s face it: There’s something oddly mystical about slow-playing bluegrass. Maybe it’s the plaintive wail of a single string instrument, held rapturously before an abrupt change of tone. (It’s the difference between a violin and a fiddle.) Maybe we project the sound wafting over fog-choked mountains that hold many secrets, or project a plain, rural lifestyle touched by sadness and hard-won humanity. It could be the folksy, homespun voices that resonate in our heads when someone sings along. There’s a story behind the strains of a hillbilly melody, even if we don’t know what it is.

Edie Brickell and Steve Martin know that feeling too well. Martin, if you’re old enough to recall, has long been a fan of the banjo, even playing it in his comedy act — a more upbeat sound than the bluegrass I’m talking about, but part-and-parcel with its heritage. Brickell, one of the forerunners of the incipient alt-rock scene of the late ’80s/early ’90s, knows root-based music well herself. (She’s married to Paul Simon, himself an advocate for world musicology.) Together, they have recorded two heritage-music album, one of which formed the seed for Bright Star, a musical now at the Winspear, chocked with bluegrass as well as some Texas swing and foot-stomping hoedown music.

The songs, and there are many, are lovely and evocative and enhance the story, although I’ll be darned if I could have whistled two bars of any one of them while I walked up to aisle to my car after opening night. It’s not that kind of music — it just keeps you in the moment, delights you and let’s you move on. I’m cool with that.

The plot has echoes of a folk tale, if not a myth or bible story. In 1945, Billy Cain (Henry Gottfried) is recently home to North Carolina from the war, and ready to start his life with aspirations to be a writer like his idol Thomas Wolfe. He approaches Alice Murphy (Audrey Cardwell), the exacting editor of the respected Asheville Southern Journal, to see if she’ll publish his short stories. Audrey takes an interest in the young man writing about life in his small town, and it takes her back to 1923, when she herself a country girl with strong opinions and a desire to write. She falls for Jimmy (Patrick Cummings), the scion of the town’s mayor and business leader. But though they love each other, their families disapprove, going so far as to conspire against the couple in shocking ways that will only resolve themselves a quarter-century later.

If you can’t see the “twist” coming from the far side of the holler, ya ain’t seen a movie in the last 60 years (or read a novel in the last 200); but Bright Star is more elemental than inventive. It benefits from Cardwell’s lovely, bifurcated performance: As the tough middle-aged editor and her callow counterpart, whose life has a novelist’s sense of irony and pain. She’s reason enough to catch this show… and to luxuriate in the charming music of Americana.

— Arnold Wayne Jones

At the Winspear Opera House through June 24.