Shelagh Hackett lost no time pulling the audience into the story her life with the first words of Kiss Me I’m Irish, her one-woman play at the Martha’s Vineyard Playhouse last weekend.

“Eleven inches. That’s what they called me,” she said, recalling her elementary-school humiliation after a boy measured her seated posterior with a ruler.

“Eleven inches! I thought it was so huge,” she added, as the audience broke into laughter. “Now it’s the width of one arthritic knee.”

A series of colorful paintings of leaping men by Ms. Hackett’s brother, Nem Hackett, hung above the simple playhouse set for the show, her first play. Directed by playhouse artistic director MJ Bruder Munafo, Ms. Hackett’s performance was a time-traveling tour of her life, beginning with her girlhood in an affluent, image-conscious Boston suburb.

“I look at pictures of myself in the fifth grade and I was perfect,” she said with a trace of sadness.

Her own mother could never bring herself to call little Shelagh pretty, and she grew up seeing herself as anything but. Ms. Hackett was girlish and vulnerable as her fifth-grade self, timidly singing Yellow Bird to audition for a Gilbert & Sullivan operetta. When she got the part, “everything changed,” she said. “I began to change my personality,” becoming more outgoing as she explored the world of performing arts.

“When I sang, I felt beautiful,” she said, before belting out her high school solo from You Light Up My Life.

She also explored her sexuality, and there’s a lovely scene in Kiss Me I’m Irish in which Ms. Hackett recalls a teenage skinny-dipping adventure on a lake in Vermont. Ms. Bruder Munafo’s understated direction had Ms. Hackett moving her arms, as if treading water, throughout the speech. Those gentle movements brought alive the budding excitement of girls swimming naked in the dark while boys canoe nearby.

Ms. Hackett picked up a clarinet to demonstrate why the instrument she played in high school is the least-flattering in the orchestra—slumping the musician’s shoulders, producing a muffin top around her middle and “turning your lovely concert maxi into a pair of culottes.”

She would have preferred the French horn, “with its elegant shape and dreamy sound.” But then, “any instrument that you blow just isn’t going to make you look good,” Ms. Hackett added, as the audience laughed.

Ms. Hackett also shared some of her adventures studying drama at New York University’s Tisch School for the Arts with Stella Adler.

“Her charm was unbelievable,” she said of the famed acting coach.

In one of the play’s funniest monologues, Ms. Hackett lay supine on the stage as she described what it was like to play Julius Caesar in last year’s all-female Tisbury Amphitheatre performance of the Shakespeare tragedy, after her character was assassinated.

While being “verbally worshiped and physically moved about,” Ms. Hackett had to remain as still as death for 30 minutes, while experiencing menopausal hot flashes as the summer sun beat down. Her interior dialogue veered hilariously from “Ants fall from trees on your face. That’s weird. Why do they climb so high?” to “My toe is twitching again in my boot. Did I remember to turn off the garden hose?”

Kiss Me I’m Irish had its soberer moments as well. Ms. Hackett’s father died unexpectedly when she was in her early 20s. She developed destructive habits: “Those demons creep up fast,” she said.

“I kicked a drug habit,” she told the attentive audience. “I was a fall-down, black-out drunk.”

After a car crash and arrest and two stints in rehab, she stopped drinking after her first pregnancy test. “Thank God for that baby,” she said.

But motherhood, “the hardest thing I’ve ever done,” had its dangers too. Ms. Hackett endured four miscarriages and, after giving birth by Cesarean section at age 39, suffered a serious, undiagnosed postpartum depression.

“Good mothers feel joy, and I felt so much fear,” she said.

Remembering her own late parents, Ms. Hackett sang How Are Things in Glocca Morra from Finian’s Rainbow and wiped away some tears. In her final scene, Ms. Hackett recalled hearing Led Zeppelin’s In the Evening for the first time after her father’s memorial service.

“I love this song so much that I have mastered one of the most difficult air guitar solos of all time,” she said.

Singing and “playing” along with the 1979 song, better known by its chorus, “Oh, I need your love,"Ms. Hackett’s attention to her air guitar’s invisible whammy bar proved she wasn’t just boasting.

The playhouse’s spring series of original one-woman shows began earlier this month with Lynne Adams’s Two Faced and Molly Conole’s Seaglass, Quilts & Song: A Life in Pieces., and concludes on May 24 and 25 with Elizabeth Parrish in Every Soul’s a Cabaret.

StageSource Boston has recognized the series with its Standing O Stamp of Approval, because all four of the plays are written, performed and directed by women and tell stories of women’s lives.

For tickets and information, visit mvplayhouse.org.