Meet Bridget Conroy, Cathleen Mullin and Jack Smythe: three characters who had been searching for an author — and full names — since they were first invented by playwright Eugene O’Neill in the 1940s. With Ronan Noone’s play The Second Girl, they have found themselves.

Mr. O’Neill’s Pulitzer-winning Long Day’s Journey Into Night, set in 1912, features the Tyrone family, who spend most of their time torturing themselves and each other with arguments, recriminations, deceit and self-deception. This unhappy Irish-American clan also looks down on their Irish immigrant servants. In Long Day’s Journey Into Night, the servants are minor characters at best. A longtime admirer of Mr. O’Neill’s work, Mr. Noone found himself compelled to speak up for the cook and maid who made the Tyrones’ lifestyle possible.

Play takes its setting from Long Day's Journey Into Night by Eugene O'Neill. — MJ Bruder Munafo

“I wanted to give a little bit of dignity to them,” Mr. Noone said.

The Second Girl, which opened last week at the Martha’s Vineyard Playhouse, does much more. Set during the same time-frame as Mr. O’Neill’s 20th-century masterpiece, it breathes voice, personality and soul into the Tyrones’ servants.

Mr. Noone moved from Ireland to Martha’s Vineyard in 1994, living and working here for six years before pursuing his playwriting career off-Island.

“If I hadn’t done that I couldn’t have written [The Second Girl],” he said.

Mr. Noone worked at the Wharf, bartended at the Harbor View and worked on painting crews during his Island years. “The emotion of uprooting yourself and beginning life afresh courses through that play. So in a way, the play started on Martha’s Vineyard.”

Cook Bridget was sketched by Mr. O’Neill as an offstage temper with a taste for whiskey. Played by Doria Bramante in The Second Girl, she emerges as an articulate, prickly and deeply wounded exile from a home and family who drinks to blot out a life-shattering loss.

“I made a mistake a while back and it determines my life from now on,” says Bridget, who still begins each day with a prayer to the Virgin Mary.

Mr. Noone built Bridget’s character from the hints in Mr. O’Neill’s play. For her more positive attributes he looked to his own grandmother.

“Not that she drank like Bridget, but her stoicism and her pragmatism and her love inspired [the role],” he said.

Portrayed in The Second Girl by Maggie McCaffery, Cathleen is the only Tyrone servant to appear on stage in Mr. O’Neill’s play. She keeps Mary Tyrone company after a morphine buy and sasses James Tyrone while tipsy on a glass her mistress urged her to drink.

High-spirited and determined, Mr. Noone’s Cathleen is far more nuanced than the original character. “I wanted to show her resilience. They always play her as kind of a bumbler and ingratiating. I wanted to take that back and show that this is a person who is quite different in the kitchen.”

Mr. Noone has made Cathleen both Bridget’s niece and a survivor of the Titanic disaster, traveling in steerage from Ireland to her job in America. “It’s difficult to refer to someone as stupid and lazy when they’ve crossed the ocean and survived a shipwreck,” he said. “The minute she goes back in the kitchen, you see an ambitious person, the person who wants to matter.”

Maggie McCaffery as Cathleen. — MJ Bruder Munafo

Played by Island resident Chris Roberts, Smythe, the driver (Mary Tyrone doesn’t consider him a real chauffeur) gets the biggest makeover in The Second Girl. The only American servant under the Tyrones’ roof, Mr. Noone’s Jack Smythe is a widower who loves Bridget with all his heart despite her drinking and bitterness. Why does he keep trying to pierce her hard shell?

“Why do we love some of those people out there against reason some times? What is it in our heart that attracts us to people who are damaged?” Mr. Noone responded. “The ineffability of that is what we can’t articulate.”

Or, as Jack says: “Man is a lonely creature.”

Directed by MJ Bruder Munafo, this production of The Second Girl has a brighter and more optimistic tone than its world premiere at the Huntington Theatre last year, which Mr. Noone called “lugubrious.”

“I wanted it to be about joy in the struggle,” he said. “You see the heartache and the hardship, and you see the light shining through.”

As in any servants hall, there are some laughs at the Tyrones’ expense.

“She’s tipsy,” Jack observes of Cathleen. “It’ll look normal to them,” Bridget responds.

But familiarity with Long Day’s Journey Into Night is by no means a prerequisite for enjoying The Second Girl, although Mr. Noone acknowledges “that’s neat if it pulls you into watching O’Neill.”

The Second Girl runs through Oct. 8 at the Martha’s Vineyard Playhouse. Performances are at 7:30 p.m. and tickets are available at mvplayhouse.org or 508-696-6300.