Hot flashes. They’re not something you see much on stage, screen, or anywhere else these days. You might hear someone crack a cheap joke about them or, even in a work as strong as “Dinner With Friends,” use them as poignant shorthand for a woman’s farewell to youth. But women in their 50s just don’t get a lot of time in the spotlight, never mind their hormonal recalibrations.

If nothing else, Wendy Wasserstein’s well-oiled but formulaic “Third” reclaims the 50-something woman as a suitable subject for a play. The title refers in part to the third and final phase of life for Laurie Jameson (Dianne Wiest), a pioneering feminist thinker and college professor. She specializes in “King Lear,” a play that she feels has been hijacked by patriarchal scholars who have demonized the two wily older sisters, resulting in “the girlification of Cordelia.” Just as Laurie yanks Regan and Goneril back into the foreground, Ms. Wasserstein does her own bit of “de-girlification” with the help of her gifted star. Ms. Wiest’s Laurie is a complicated, blinkered, tender woman with her own psychological blind spots – and, yes, her own hot flashes, a state that Ms. Wasserstein and director Daniel Sullivan unapologetically introduce in the very first scene.

Laurie teaches at an unnamed New England liberal arts college, with an emphasis on “liberal”: It boasts of having the nation’s first transgendered dorm, and Ms. Wasserstein wrings close to a dozen jokes, many of them a bit creaky, out of its absurdly diverse student body. (Thomas Lynch’s versatile set turns the Mitzi E. Newhouse thrust stage into a sort of college quad in reverse, with patches of grass surrounding a central stone square.) But in fall 2002, with war in Iraq all but inevitable, Laurie’s anxiety over the political climate can’t be mollified anymore by just shouting at CNN. And so she shifts her anger at the Bush administration toward one of her students.

By all outward appearances, Woodson Bull III (Jason Ritter) is the embodiment of what she’s against – “a living dead white male,” as he calls himself. (“Third” is also Woodson’s nickname.) He’s a varsity wrestler and a legacy student, he reads “Harry Potter,” and he might even be a Republican. His boyish forelock and polite affect only seem to rile Laurie even more, but the last straw comes when Woodson dares to submit a midterm essay on the Freudian psychosexual motifs in “King Lear” that’s actually good. “It’s the work of an advanced scholar,” she sputters, “not a wrestler, even from Groton.”The white male becomes Laurie’s white whale, as she devotes her energies to finding the enigmatic, affable Woodson guilty of plagiarism.

Woodson, and specifically Laurie’s reaction to him, is the biggest problem in “Third.” Can this really be the first moderate, let alone conservative, student to cross her path? Or just the first one with any intelligence? Even if Woodson is catching her at a vulnerable time, virtually every college has a fervent (if sometimes small) Young Republican branch, and a school that prides itself this much on its diversity is bound to attract some kids who tack right just for the sake of argument. Mr. Ritter skillfully keeps Woodson from becoming too much of a puppyish naif or a undermining schemer – he seems to share with his character a fondness for not being categorized too quickly – but Woodson’s qualities as an ideological sparring partner quickly swamp the character.

Ms. Wasserstein has drawn from a variety of sources: The confrontation between a blinkered authoritarian and a threatening “new” mind-set takes a page or two from “Doubt,” and the pair of academia-hot-potato plays “Spinning Into Butter” and “Oleanna” also make their presences felt. The more surprising resonances come from “King Lear” itself, as Laurie becomes a sort of Cordelia to her father, Jack (an underused Charles Durning), who has been reduced by Alzheimer’s disease to a confused rage.

This also isn’t Ms. Wasserstein’s first glimpse at New England academia. In the published version of her “Uncommon Women and Others,” she has this to say about one of the play’s 1972 Mount Holyoke graduates: “Sometimes Leilah spends a great deal of time alone being admirable.” Laurie has taken a similar path, but rather than do their part and admire her, her (unseen) husband lifts weights upstairs, her father slips deeper into unintelligibility, and her daughter Emily (Gaby Hoffmann, who also doesn’t have much to work with) prowls the bars every night during her visits home.

The best part of “Third” is the unusual amount of space devoted to its smug, frightened, kindhearted, vindictive, blazingly human heroine. Ms. Wiest is in almost every scene and finds the right tempos and tones for each one, providing Laurie with a passion for intellectual honesty that ennobles her even as it misleads her. From a plausibly scattered therapy session to a hallucinatory examination of her motives to a trio of reconciliations at the end, Ms. Wiest folds the audience into her arms – and then shrewdly pushes them away when it’s in the play’s interests. It is a performance to cherish.

Ms. Wiest is, however, frequently undermined by Ms. Wasserstein’s ba-dumbum comic rhythms, especially in scenes that warrant more heft. (The scenes with Jack thrust Mr. Durning into a particularly uncomfortable limbo between humor and pathos, a rare miscalculation from Ms. Wasserstein’s frequent collaborator, the usually surefooted Mr. Sullivan.) Laurie’s fulminations against President Bush and the Christian right have a preaching-to-the-converted feel, and she limps to the finish with those three consecutive scenes of Laurie making peace with just about everyone. Each of these scenes hits all the necessary markers, but it’s done so mechanically, so dutifully, that not even Ms. Wiest’s interpretative gifts can make them dramatically satisfying.

Ms. Wasserstein is just about incapable of being unentertaining, and her snug blend of drollery and drama may be enough to satisfy longtime fans. But she shows herself stubbornly content to tiptoe toward larger problems – why liberals insist on dulling their power by fighting the wrong battles, how dying parents can force a re-examination of one’s art and life – and then to fall back on her warm-bath laughs and tidy resolutions. Laurie Jameson and Woodson Bull III are clearly ready to dive into a knock-down-drag-out intellectual brawl. But they’re too busy learning from each other to ever take their gloves off.

Until December 11 (150 W. 65th Street, 212-239-6200).