Gregory Perri and Lorene Chesley in Lydia R. Diamond’s "Smart People," at Arena Stage. (C. Stanley Photography)

A tidy geometry of gender and race takes shape right away in the Arena Stage production of Lydia R. Diamond’s bright, acerbic comedy “Smart People.” Two men: one black, one white. Two women: one black, one Asian American. See how different combinations of ethnic and/or sexual lines parallel, bisect or glance off in tangents.

Or maybe chemistry is a better parallel. Set these elements in the heady environment of Cambridge, Mass., as Barack Obama first campaigned for the presidency, and make the white guy – named Brian White — a liberal, egotistical Harvard neuroscientist on the verge of proving that racism is not simply a cultural construct but is in fact biological.

Notice the increasing heat, and how this single element invariably converts friendly banter and even romance into flame-throwing arguments.

Goodness, such smart people! Ginny Yang, who declares that she’s half Chinese, half Japanese, is a research psychologist specializing in cultural stereotypes. Valerie Johnston just finished a master’s in acting, which means her code-switching is expert as she bounces between classical characters and ghetto caricatures. Jackson Moore is a handsome, proud young doctor plainly battling discrimination at the hospital. And of course angry, sarcastic Brian White “gets it” about race, though he’s tired of having to explain that to even his smart friends. After all, they’re hardly neuroscientists.

“Smart People” doesn’t muddle much with subtext: This is the sort of comedy where everyone is completely capable of saying exactly what they think. That should be an advantage, but the dialogue is oddly delivered at lecture hall levels in Seema Sueko’s visually slick production in the Kreeger Theater. The house style at Arena isn’t subtle — see the emphatically entertaining “A Raisin in the Sun” now playing across the hall — and you’ll spend the early portions of this show admiring the candy-colored light boxes of Misha Kachman’s unfurnished set, yet also wondering why the actors are speaking like public address announcers.

Luckily, Diamond’s dialogue is as clever as the title promises, and her characters press through initial assumption-laden encounters to — well, whole new levels of assumption-laden encounters. It’s a funny play: “My politics are such that I can make that joke,” Brian says to Ginny over a drink after making a dubious wisecrack. Ginny quickly corrects him during the type of competitive intellectual banter that would be vastly more amusing if the performances settled into the rough, unexpected edges of its people from the start.

Lorene Chesley begins to thaw the frosty, vaguely clinical show when the edgy Valerie goes to Jackson’s for dinner. “I’m not slick,” Valerie says at one point, and once Chesley begins mixing Valerie’s vulnerability with her knee-jerk fury as Jackson accuses her of acting “sadiddy,” a delectable comic performance starts to shine.

Jaysen Wright hits his stride at about the same time as the eerily smooth Jackson, adding laid-back but deadly barbs to his rigid portrait of a man with a hidden soft heart and a necessarily steely spine. Once Chesley and Wright tap into their characters’ love-hate chemistry, the show finally starts to be not merely interesting, but genuinely entertaining.

The science of race: “Smart People” at Arena Stage. (C. Stanley Photography)

Brian’s controversial theory is the script’s catalyst, along with a personality that stands out as entitled even among this cocky quartet (putting an asterisk on Valerie’s variable confidence). Gregory Perri is most persuasive when Brian lashes back at his unseen Harvard critics and his increasingly aghast friends, particularly when challenged about whether his research might lead in directions that fascinated Nazis, too.

Sue Jin Song’s Ginny is every bit as arrogant as Brian, though there appear to be more shades in Diamond’s portrait than Song plumbs. Song’s wrath is formidable, though, during one of the play’s most explosive scenes, with Ginny unleashing a nasty bit of role-play on Brian as they stumble in and out of bed. The sudden blitz of projections in Jared Mezzocchi’s design drives home the mash-up in Brian’s head, but the visual barrage also crosses the line from mind-blowing to headache-inducing.

A flurry of related plays may dance in the minds of dedicated D.C. theatergoers, from Tearrance Arvelle Chisholm’s equally sassy “Hooded: Or Being Black for Dummies” to Stoppard’s science-driven “The Hard Problem” and Ayad Akhtar’s “Disgraced,” performed on the Kreeger’s stage at this time last year. Like “Disgraced,” “Smart People” culminates in a four-person dinner party that erupts on demographic lines, and you can hear different pockets of the audience laughing and gasping when the truth-telling insults inevitably get served.

The “Disgraced” performance was more supple, and at over 2½ hours you eventually feel this show’s length. Diamond’s knowing, rational, witty voice steadily persuades you that her comedy of ideas is onto something, even if this earnest production seldom wears its learning lightly enough.

Smart People by Lydia R. Diamond. Directed by Seema Sueko. Costumes, Dede M. Ayite; lights, Xavier Pierce; sound design, Andre Pluess. About 2 hours 40 minutes. Through May 21 at Arena Stage, 1101 Sixth St. SW. Tickets $40-$111, subject to change. Call 202-467-4600 or visit