SO THERE'S this old Brazilian joke, by now so familiar as to hardly bear repeating:

Por que os homens na cama sao como comida de microondas?

Estao prontos em trinta segundos.

Go ahead, laugh. I'll give you time to recover.

Wait -- you say you don't speak Portuguese? No matter! Just imagine the best interrogative setup (a la "Why did the chicken cross the road?"), followed by a punch line that's surprising, wry and somehow inevitable, and then imagine the whole thing being uttered by Matilde, the Brazilian maid at the immaculate center of Woolly Mammoth's "The Clean House."

Laughing yet? You will.

"Everyone in this play should be able to tell a really good joke," commands playwright Sarah Ruhl in her opening stage directions, as befits a comedy whose characters have an almost fanatical faith in the power of humor. ("A good joke cleans your insides out," Matilde says.) But like the word "clean," which is usually defined by what it's not (stain-free, spotless), a joke is only as good as the painful truth out of which it springs, so don't go expecting a laugh riot. "The Clean House" is a "Heartbreak House."

It is also the house of Lane (Naomi Jacobson), a fifty-something doctor who lives with her husband, Charles (Mitchell Hebert), also a doctor, in a "metaphysical Connecticut" of absolute sterility. The living room is all white, from lamp to rug. Hence the necessity of Matilde (Guenia Lemos). But there's a problem, as Lane informs us in the play's opening moments.

"My cleaning lady -- from Brazil -- decided that she was depressed one day and stopped cleaning my house.

"I was like: Clean my house!

"And she wouldn't!"

This, as it turns out, is only the first of many frustrations Lane will have to endure in an evening whose issues start small but quickly grow to include jealousy, infidelity, the inevitability of death and the healing power of chaos. In other words, the dirt piles up.

"It feels like it's speaking to a quintessentially American question about how we deny the messiness of our lives," says Rebecca Taichman, who is directing the Woolly production. "We like to take the dirtiness and the complications and sort of suck them out of life, or try to."

It's the of-the-moment quality of "House" that accounts, in part, for the tremendous buzz surrounding Ruhl, whose comedy accomplished the not-inconsiderable feat of becoming a finalist for this year's Pulitzer Prize without ever having received a New York production. Just 31 years old (a prodigy as playwrights go) and based far from the eastern theater establishment (in Los Angeles), Ruhl has nevertheless found a small but growing following, thanks to, as Taichman puts it, "an extraordinarily unique kind of poetry. . . . She puts the quirky and the epic and slams them up next to each other."

Out of that collision comes several oddly wonderful stage pictures -- a balcony love scene, a shower of apples, a living room turned into an "operatic mess" -- that propel the play away from shtick and into territory more ineffable. The term one normally finds associated with this is magical realism, and Ruhl's work has been compared to that of Gabriel Garcia Marquez and filmmaker Pedro Almodovar. But there's a great tidiness to the way "House" approaches messiness, an economy of language and a refreshingly delicate approach to the Big Questions lurking on the periphery.

As a bonus, you'll never feel guilty about living like a pig again.

"If I were to die at any moment during the day, no one would have to clean my kitchen." So says Lane's sister Virginia (Sarah Marshall), who, as a card-carrying member of Ruhl's universe, must possess a deeply personal view of housework. To Virginia falls the potentially unhappy task of philosophizing on dust, a substance that in all other worlds save the playwright's connotes something small, insignificant and powerless. Accordingly, Virginia offers a revisionist view.

"If you do not clean, how do you know if you've made any progress in life? I love dust. The dust always makes progress. Then I remove the dust. That is progress.

"If it were not for dust I think I would die."

Virginia (Sarah Marshall, left), Lane (Naomi Jacobson), Charles (Mitchell Hebert), Ana (Franca Barchiesi) and Matilde (Guenia Lemos ). Virginia (Marshall) and Matilde (Lemos) work in "The Clean House."