PLENTY," AT Arena Stage, has generated a few audience reactions the playwright probably never anticipated.

"You must tell us about life in Iran," the play's diplomat-hero is asked, and he answers by describing the Iranian people ("fine insofar as one's seen them"), the poverty, the sky and the beauty of the desert. In sum, "I would say we'd been very happy out there," he says. ". . . I think the peace has done us both a great deal of good."

England's David Hare wrote "Plenty" before the Iranian revolution, so no irony was intended in this restful description of a foreigner's life in Tehran. But the play's abundance of references to world events is no fluke -- and it's startling. "Plenty" is not a political play by a long shot. It's a grim love story about a man and a woman who can't possibly satisfy each other, sliding separately toward bad ends. But their hopelessness is set against, and linked to, the consumerism, the bureaucratization and the impotence of the Western world (Britain in particular) since World War II. In both spheres -- the personal and the public -- "Plenty" casts a stark light on the ugly side of 20th century life and refuses to dispense any balm of reassurance at the end.

By itself, "Plenty" is an obstinate exception to the ruling position of domestic, sentimental, "I'm O.K. -- You're O.K." evenings in the American theater. But Arena has not been content with one such act of defiance. Slawomir Mrozek's "Emigres," which opened Wednesday at the Kreeger Theater, is another work by a man whose vision extends beyond the living-room hearth, who insists that individual fulfillment has a vague something to do with the problems of humanity in general, and who feels no obligation to leave his audience brimming with self-confidence as they rise from their seats.

That two plays of this sobering ilk should have found their way into the city's current roster of theatrical entertainment is amazing -- and Arena should be saluted for it. But it is still two against untold legions.

In a speech at Georgetown University two weeks ago, playwright (and Georgetown alumnus) John Guare deplored the "softness and limpness" of the American theater. The original ending of "A Chorus Line," he recalled, had the director rejecting his most talented applicant because she just wouldn't blend in. But actress Marsha Mason, after seeing a preview, told "A Chorus Line's" Michael Bennett the ending was too depressing -- and he changed it. ("The truth is that Cassie would not get the job," Bennett later told an interviewer, "but Marsha told me, '. . . You can't take starting-over away from people.' And it made sense to me.")

"Chapter Two," a play by Mason's husband, Neil Simon, showed the same impulse to go easy on the audience, to keep it, in Guare's words, "at a handy, manageable distance." "How extraordinary," he exclaimed, "to have a play all about grief that never once makes you feel sad!"

And "The Elephant Man," he pointed out, "is about somebody who is horrifying, somebody who's repellent to look at. However, that person is played by someone who looks like they have escaped from the catalogue of the Yale Yearbook . . . Somebody who'll be the president of the student body puts his arm out and everybody on the stage is repelled by this person -- except the audience is allowed to say, 'Ah, only we are sensitive enough to see how beautiful elephant man really is.'"

Producers are out to flatter audiences and, at all costs, not to threaten them, Guare complained. But he never specified how he would have cast "The Elephant Man" -- and it may have been just as well. If its producers had tried to produce a reasonable physical approximation of John Merrick (the real-life 19th-century man on whom the play was based), the results -- in the present state of cosmetics -- might have been more ludicrous than threatening. Still, not every manifestation of an objectionable pattern must be objectionable in itself.

Had Guare been in Washington the last few years (instead of teaching drama at Yale), he could have found a few million barrels more fuel for his argument. There were the big musical revivals, of course -- "Oklahoma," "Peter Pan," "West Side Story." What could be less threatening to an audience than a familiar entertainment from times gone by? But even in new works, and in serious ones, and in ones with (theoretically) unpleasant subject matter, there was the same tendency to smooth things over and shut the door on the outside world.

Ironically, this tendency has coexisted with a new interest in disabilities, deformities and aging. In the last few years the theater has fumblingly tried to make up for generations of indifference to these problems -- while dressing them up, again and again, in the cutest possible clothes. Hence, in "Charlie and Algernon," we had the phenomenon of a musical about mental retardation; but the retarded hero was the most gentle, undemanding, easy-to-take retarded person you could hope to meet.

Even in a play as innocent as "The Kingfisher," the author's one bold notion -- a love affair between two people in their 70s -- was jettisoned by having Claudette Colbert, as the lady in the case, look so glamourous and nimble that no ordinary septuagenarian could think of herself (or be thought of) in the same breath. (The prostitution profession probably had a similarly tough time recognizing itself in the gentle surroundings of "The Best Little Whorehouse in Texas.")

By persistently sweetening up life's bitternesses and ignoring history and current events, the American theater surrenders any claim to be a major artistic force. It wants to tell us heart-warming personal stories that have no bearing on anyone but the characters involved. It is catering to an audience that is pleading, as Guare has put it: "Please, God, I'll pay any money as long as the play stays up there and doesn't come across the footlights and get into my life."

Arena's "Plenty" is unsuccessful by one standard -- a basic one, unfortunately. The heroine who skips across the ambitious tapestry of its 12 scenes is not, finally, a deeply involving character. Susan, the former French resistance fighter who can't find a place worthy of her in post-war Britain, represents a malaise and a cold yearning that is real, widespread and frightening in the industrial world. But "represent" is a verb that won't cut it onstage -- a character must simply "be." And Susan, while played by an extremely skilled actress named Blair Brown, somehow isn't.

Nevertheless, the play "comes across the footlights." Brock, the diplomat who falls in love with Susan and devotes his life to her, is a recognizable and genuinely poignant character (and admirably acted by John Glover.) He's a bit of a bumbler, but he knows it. When the ever-idle Susan ridicules his job, his boss and the entire British foreign service, Brock can only acknowledge that "of course our people are dull, they're stuffy, they're death -- but what other world do I have?" Through his plodding, bureaucratic, step-by-step existence and Susan's self-indulgent, irresponsible detachment, "Plenty" poses a choice between two alternative life plans with an immediate and scary meaning to almost any theatergoer -- especially in this over-affluent, government-supported city.

The two characters of "Emigres" are not, in the abstract, so easy to identify with. Both are Eastern European exiles who have gone west -- to a dingy basement apartment somewhere in West Germany -- in search of freedoms neither can fully define. But the play's absurdist humor is very agreeable, and Stanley Anderson and Richard Bauer give sensational performances that greatly smooth the cross-cultural journey.

"Emigres'" author is Polish. "Plenty's" author is British. American playwrights -- and audiences -- may have a thing or two to learn from them.