PLENTY by David Hare; directed by David Chambers; scenery by Ming Cho Lee; lighting by William Mintzer; costumes by Marjorie Slaiman; music by Nick Bicat.

With Blair Brown, Joan MacIntosh, John Glover, Timothy Jerome, Jean-Pierre Stewart, Ernest Graves, Robert Thaler, Cary Anne Spear, Tom Matsusaka, Anne Miyamoto, Christina Moore, James Jerome, Terrance Currier and Joe Palmieri.

At Arena Stage through May 11.

'Plenty," which bowed at Arena Stage last night, is sure to provoke extreme responses -- laughter, discomfort, confusion, disappointment and wonderment to name a few. And that's as it should be, for David Hare has written a funny, discomforting, confusing, disappointing and wondrous play.

It is an episodic portrait, spanning 20 years, of a woman on a constant prowl for adventure and yet fatally convinced the world has nothing to offer that is worthy of her. For one shining hour, she fought with the French Resistance in World War II and felt challenged and uplifted, but nothing afterward can measure up -- neither her work, nor men, nor England in its bumbling postwar decline.

At one bored moment, she decides to rent a man to father a child for her, having concluded that to actually live with a man would be intolerable. She is so "strongminded," she explains, that with most men of her acquaintance, "I'm holding myself in for fear of blowing them out of the room."

But the lower-class fellow she chooses for her stud protests that this can't be what she wants, "not deep down."

"No," she replies. ". . . Deep down I'd do the whole damn thing by myself. But there we are.You're second best."

No child comes of this liaison. It is just another of the disappointments that gradually accumulate into madness. She marries a diplomat, but his plodding devotion to her -- and to duty -- serves only to dot the i's and cross the t's in her indictment of the sex, the nation and the world order he represents.

Within this intriguing framework, Hare's play and the Arena production offer many concrete pleasures and abstract virtues.

Hare is a playwright who goes against the grain -- and more power to him! While his contemporaries are imitating the short, repetitive rhythms of Harold Pinter, he exercises a much wider range of rhetorical options. "Plenty" abounds with the kind of rich, long speeches that have almost vanished from the theater, and they come gracefully and compellingly off the tongues of Blair Brown, John Glover, Joan MacIntosh and Ernest Graves, the four fine actors with the principal roles.

While his contemporaries focus on ever-narrower, ever-more-domestic subjects, Hare locates his story in a fully defined period and culture. More than that, he writes, simultaneously, about a small circle of friends and about that abstract enormity called Western Civilization.

The grievances of Susan Traherne, "Plenty's" heroine, are the grievances of all who skeptically search the 20th-century Anglo-American horizon for challenge that are worthy of us.

On most of the occasions when dramatic, characters suffer bouts of insanity, the thing bears little relation to any behavior observed in real life. We sit back patiently and wait till the playwright and the performer have finished their desperate efforts to convince us someone is going crazy. We struggle, perhaps, to give both the benefit of the doubt, if the rest of the play seems worth waiting for. But "Plenty" makes mental illness something credible and comprehensible -- almost something ordinary .

That's another of the play's great virtues, for which director David Chambers and star Blair Brown are entitled to a large share of the credit alongside the author. Unfortunately, when the heroine is not having one of her fits -- when she is, to outward appearances, behaving sanely -- "Plenty" tends to become stiff and superficial, exasperatingly so. And the blame for what's wrong ought to be apportioned as diversely as the credit for what's right.

Hare, to begin with, has simply not plunged deeply enough into the spirit and psyche of his heroine. Too much about her is taken for granted -- including details and character shadings that established early, might make us care more about the distress that later overtakes her. We learn more, it seems, about the Suez Crisis than about Susan's origins and aspirations.

If the play itself has more scope than depth, that may be true of the production too. Chambers has a cinematic eye and a love of physical derring-do that occasionally stand in the way of a close relationship between characters and audience. But for the most part, the visual richness of his actors' concern for the words and emotions that are the basic stuff of the play.

As Susan, Blair Brown has several enthralling scenes that show us an enormously gifted actress. But the brittle veneer she affects when her character is acting normally -- when nothing special is afoot -- is occasionally wearying and off-putting.

Those whose ears are supersensitive to discrepanciees in English accents will have complaints to lodge about the supporting performances. But Ernest Graves as Darwin, a haughtly diplomat who, late in the play, reveals a conscience we never thought was there: John Glover, as the husband; and Joan MacIntosh, as Susan's Bohemian best friend, give strong, finely tuned performances. Graves, in particular, is the haughty Englishman to end all haughty Englishmen -- and he has a speech or two worthy of Noel Coward or Bernard Shaw.

In the confusing hodgepodge of its virtues and defects, "Plenty" is not an easy production to evaluate. But it is well worth thinking about, which is a notable virtue in itself.

(Caveat postscript: This production includes two brief but flamboyant scenes of male and female nudity.)