When a work of theater focuses exclusively on the lives of older women — the things that pain them, humiliate them, terrify them, strengthen them, elate them, or amuse them — it’s instantly marginalized. Unless they’re gargoyles or saints, older women are typically on the periphery, and their courage and self-actualization are matters that most audiences ignore. They’re taken seriously only through the eyes of someone else.

That’s why “Wrinkles, the Musical,” with a book and lyrics by Naomi Turner and Wilderness Sarchild and music by Malcolm Granger, is such a worthy project. It began when Turner and Sarchild, both Cape residents turning 60, interviewed more than 100 other older women and turned the stories they heard into a 30-minute work-in-progress performed at the Wellfleet Harbor Actors Theater in 2010. With songs set to music by Granger, it eventually became a full-length musical with a strong narrative arc. It premiered in 2017 at Cape Cod Theatre Company, returned in 2018, then went back to workshop for refinements. Now it has arrived at WHAT with a marvelous cast of seven Equity actors, directed by Dani Davis, for a two-week run ending Oct. 27.

The premise is simple enough: it’s a putting-on-a-show story (the show being “Wrinkles, the Musical,” reflexively) set in a senior community in Central Florida. Aja (Leslie Becker), a retired drama teacher, is the prime mover. She recently relocated to the area with her wife, Sal (Julia Lema), a musician and performer, to be close to her aunt Beulah, whose hobby, it seems, is the pagan spirituality of goddesses, witches, and crones.

The show begins with an early meeting of the play-within-the-play’s cast. Along with Beulah, there’s Ms. D (Susan J. Jacks), a brash, thrice-married straight shooter; Pam (Diane J. Findlay), a widow and former best friend of Ms. D’s who hasn’t seen her in decades; Val (Barbara McCullough), a southern belle who’s dating a 33-year-old Swede — a man younger than her daughter; and earnest Louise (Gael Schaefer). Each of them has a story to tell, issues to resolve, and songs to sing.

Aja’s story is tragic: though she came to Florida to see to her aunt, she develops her own health issues, which threaten the musical and test her relationship with Sal. Also heart-rending is the plight of Louise, whose daughter has met a sad fate. Then there’s the tentative rapprochement of Ms. D and Pam, whose close friendship ended when Pam inexplicably abandoned it. We learn of people’s backgrounds as the rehearsal process unfolds — through diaries, confessions and confrontations — and to Turner’s and Sarchild’s credit, the “Chorus Line”-like progression of individual stories doesn’t feel schematic or forced. There are moments of sitcomish “Golden Girls”-style humor (from farts to sexual innuendos) and a few predictable lines (complaining about men), but the authors largely avoid the clichés that often infect this kind of well-meaning theater.

The real gift of “Wrinkles, the Musical” is the way the seven women are individuated and developed as characters, and the inspired performances of the entire cast. You never mix them up, and even while singing and dancing they perfectly inhabit their characters’ personas. Leslie Becker is thoroughly believable as the saintly troupe leader, Aja. Perhaps she’s too saintly — can a person be so free of selfish motivations? — but Becker makes it work. Her interactions with Julia Lema’s Sal, whose common sense and earthy warmth contrast nicely with Aja’s polite poetic musings, ring true as well.

Barbara McCullough, as the flirty Val, handles comic relief with charm; her duet with Susan J. Jacks’s Ms. D on the joys of plastic surgery is refreshingly vain and shallow. The standout performance is Diane J. Findlay’s Pam, whose eleventh-hour number, “Do Not Resuscitate,” explodes with much-needed anger. The song goes a long way toward explaining her estrangement from Ms. D and how they might have been friends in the first place. Frustration and rage are in short supply in “Wrinkles, the Musical,” and owning those negative feelings is a feminist issue that isn’t really addressed.

WHAT’s executive and artistic director, Christopher Ostrom, has created a lovely, functional set of shifting white-wood panels for “Wrinkles,” and director Davis, musical director Peter Hodgson, and choreographer Owain Rhys Davies keep things moving briskly. The musical numbers are sweet and clever and not especially memorable, but they are well integrated into the story, which keeps the two-hour (with one intermission) running time from dragging.

It takes courage to explore and elevate the quotidian issues of older women’s lives, and a fair amount of skill to give them dramatic weight. Kudos to Turner and Sarchild for doing so, and to WHAT for giving homegrown talent the professional gloss it deserves.

Seven sisters

The event: “Wrinkles, the Musical,” book and lyrics by Naomi Turner and Wilderness Sarchild, music by Malcolm Granger
The time: Wednesday-Saturday at 7:30 p.m.; Sunday at 2 p.m.; through Oct. 27
The place: Wellfleet Harbor Actors Theater, 2357 Route 6
The cost: $25-$40; seniors $22.50-$36; students $12; at what.org