Meet the LeVays, an upper-crust African American family summering, as always, on Martha’s Vineyard. They go to pieces in funny and volcanic ways in “Stick Fly,” the nuanced, timely drama by Lydia R. Diamond.

It’s a laid-back sort of “parlor play,” Diamond suggests, that deftly pushes the American hot buttons of race and class. Yet the 39 year old playwright says she came to this up-to-the-minute consideration of love, anger, and cultural pressure – possibly the most intriguing entry in this year’s Contemporary American Theater Festival – as she was trying to unwind.

“I wanted a break,” Diamond says from Boston, fresh off a few days in Shepherdstown. She began “Stick Fly” as she was finishing “Voyeur de Venus,” based on the South African woman Saartje Bartman (demeaningly exhibited across Europe in the 19th century as the “Hottentot Venus”). “It was one of those emotionally difficult plays to write,” Diamond explains of “Venus,” “a lot of horribly depressing, sad research.”

“Stick Fly” brought Diamond back to what made her a playwright in the first place: the desire to create the kinds of contemporary roles she wasn’t seeing much as a theater student and actress at Northwestern University. Who were the writers of color? Where were the modern topics? Diamond wasn’t seeing them much – “complicated, interesting, funny, flawed dramatic characters,” she says – either in school or afterward as she plunged into the thriving Chicago theater scene.

“I don’t want it to seem like I thought, or think, I would be The Deliverer of Good Roles to Black Women,” Diamond says. “Because I know better. But at that time, I didn’t know better. I had all the gumption of a 20 year old, 22 year old, and I wanted to contribute. And I wanted to play a certain sort of role that I wasn’t finding for myself.”

That gap persists, even at the highest and most progressive levels of the theater. For all its forward-looking nature, the CATF has produced very few plays by black women. And while things appear to be looking up on Broadway, with Hollywood actors such as Morgan Freeman (“The Country Girl”), Terrence Howard (“Cat on a Hot Tin Roof,”) and Lawrence Fishburne (“Thurgood”) headlining plays this spring, the topics aren’t of recent vintage. And those dramas are by white writers.

Even in regional theaters, Diamond says, “My sense is that there’s a collective comfort zone around stories about African Americans that have an historical perspective.” She has explored that terrain herself in “Venus,” in “Harriet Jacobs,” adapted from “Incidents in the Life of a Slave Girl” for Chicago’s acclaimed Steppenwolf Theatre, and in her adaptation of Toni Morrison’s “The Bluest Eye,” which has been produced in theaters from San Francisco to Washington, D.C.

Diamond continues, “A critical discussion about race and class can potentially put an audience in the position of feeling critiqued, right? . . . I just know that culturally, as advanced and sophisticated as we feel we are, particularly with Obama running for President, we’re all feeling pretty good about ourselves. But we still don’t know how to synthesize and talk frankly, and not in an uncomfortable and defensive way, about race. We just don’t. And that makes plays that live in that arena, I think, a scary proposition for a producer.”

She stops and laughs apologetically, sounding a bit abashed. “Do I talk too much for interviews? I think I have to learn how to talk in shorter sentences.”

Her characters in “Stick Fly” have that same thoughtful, probing quality, though they’re more flip and combustible than the cool, collected Diamond seems to be. And they share elements of her background: a milieu of higher education (the adult kids are all from rich professorial stock), and the theme of absent fathers.

Diamond’s parents divorced when she was young, and she was raised by her mother, who pursued her own education and taught in universities. Childhood was college towns, from Carbondale, Illinois and Itta Bena, Mississippi to Amherst, Massachusetts. She went to Northwestern for theater, and figured she would act.

And act she did, in college and beyond, only gradually realizing that playwriting was her niche. She started her own troupe and gave it a youthfully robust name (Another Small Black Theater Company With Good Things to Say and a Lot of Nerve Productions), and then was a founding member of the Onyx Theatre Ensemble.

“Because she was an actor, she knows what it means to write a great role,” offers “Stick Fly” director Liesl Tommy. “The pace is very fast, it’s very funny, and all of the actors get something juicy to do.”

But not until she hooked up with Chicago Dramatists did Diamond begin to grasp what it meant to be a working writer.

At last, she says, “I understood that people wrote plays and sent them to theater companies and got rejection letters and applied for grants, and all the stuff that playwrights do. I hadn’t had a model for that prior to stumbling upon Chicago Dramatists.”

Her first big exposure came at Chicago’s Goodman Theatre, which produced “The Gift Horse” in its 2001-02 season, and her career took root. In 2006, “Voyeurs de Venus” and “Stick Fly” both earned nominations as best new play from Chicago’s Joseph Jefferson Awards; “Venus” won.

By then, though, Diamond had already moved to Boston, where she teaches playwriting at Boston University and lives with her husband, Harvard University sociologist of education John Diamond. She was a playwriting fellow at Boston’s Huntington Theatre Company, and is working on a commission for that troupe (as well as for New Jersey’s McCarter Theatre, which produced “Stick Fly” last fall).

“There isn’t a cliché about her,” says Jim Petosa, head of Boston University’s School of Theatre. (He is also the artistic director of Maryland’s Olney Theatre Center.) “These are sophisticated characters looking at these issues. She takes it to a different place.”

Being in Beantown is partly how she knows the exclusive “Stick Fly” setting of Martha’s Vineyard, which is enough of a bastion of African American old money that MTV came sniffing around its Oak Bluffs enclave two years ago, scrutinizing its potential for a reality series.

“There’s always someone in our circle who says, ‘Oh, we have a place on the Vineyard, you’ll have to come stay with us for a while,’” Diamond explains. “But we are not people who have a place on the Vineyard. My proximity is more like Taylor’s than the LeVays’.”

In “Stick Fly,” Taylor is the outsider daughter of a prominent intellectual; she comes to the LeVays’ for the first time as the girlfriend of the youngest son, an aspiring writer. It’s Taylor who articulates what the title means: how entomologists fasten flies to examine precisely how they move.

“I thought, ‘That’s a metaphor around which a play needs to be written,’” Diamond recalls thinking when she heard that information on the radio.

Diamond sees it all through what she consistently calls her “lens”: “I think my lens tends to be pretty racially charged,” she says, “and I tend to be interested in the contradictions societally that we have around race and class and sexuality.” (The play’s romantic liaisons are deeply tangled.) “So those are the themes that come up again and again. I’m not necessarily exploring those on purpose, or with a mission. But they pop up in the relationships because they pop up in my relationships, and in my world.”

Her world changed significantly with the birth of her son, now four, casting things that “I really thought were relatively black and white in shades of gray,” she says. “Which I think makes me a better playwright, because it makes me a better person . . . And I also think it has to do with my age. I’ve just reached a level of maturity that has slightly less conviction than my younger self did, which makes, I think, for more complicated plays, and more interesting people, and less agenda.”

Yet her voice grows wholly animated when she talks about the current political moment. Will having an African American running for President influence how audiences will view her play?

“It is for me a wildly exciting time right now politically,” Diamond declares. “I’ve never felt so much a part of the political process, or so charged about what’s happening in my country, and such a sense of ownership – which is more complicated than just a racial inclusivity. But back to what I talk about, which is the lens through which I write these plays: yes! Yes, everything – the temperature of everything – everything touches everything. So absolutely, having a candidate on the ticket that some people in the country might never have thought we’d see, it absolutely affects the way people sit in their chairs in the audience and receive whatever they’re receiving. But I don’t know how. It’s just exciting.”

Playwright Steve Dietz joins the Contemporary American Theater Festival this summer for a stage reading of his play Yankee Tavern, Tuesday, July 15 at 7pm. Yankee Tavern is a dramatic thriller about a young couple and an old codger in a tavern in New York.  “As the couple tries to debunk Ray’s outlandish theories, they find themselves caught up in what might be the biggest conspiracy of them all, showing what you don’t know can hurt you,” stated Dietz.