Strange how the American drama has often used the neighborhood bar as a stand-in for purgatory.

The thought occurred to me once again as I was leaving Woolly Mammoth's curiously comic, curiously bizarre, but definitely one-of-a-kind production of John Patrick Shanley's "Savage in Limbo."

Bars are, of course, terribly convenient from the dramatist's point of view. Anyone can wander in and rustle up a drink. Defenses crumble and confessions come easily, or at least easier than they do at a tea party.

Conviviality is what the bar presumably offers. (Isn't "happy hour" the come-on?) But more often than not, the patrons are looking for something else -- solace, a way out of the confusion of their lives, forgiveness for their sins or, failing that, forgetfulness. The characters in "Savage in Limbo" are certainly wondering how to move down a road on which there seems to be no arrows, no signposts, no green lights.

Chief among them is Denise Savage (Grainne Cassidy), a 32-year-old virgin from the Bronx. Barreling through the door, she announces that she has just eaten "two Cornish game hens and a bunch of broccoli," thereby indicating in her aggressively offbeat manner that she is primed for action.

Shanley's title suggests just how far she will get in her attempts to change a life that has more deadness than aliveness in it. (For that matter, so does a quick glance at the withered plants that dot Lewis Folden's set.) What makes Shanley's play notable, however, is the screwy energy it emits as Savage leads her one-woman charge against the status quo and stirs up her bar mates to similarly addled states of frenzy.

We could be at a particularly odd session of group therapy, just as it lifts off for outer space. Wherever we are, it's obvious that Shanley is ushering us several steps beyond naturalism. This raucous, dizzy, topsy-turvy comedy may employ the idiom of the Bronx, but its core is pure metaphysics.

"Everybody forgets everything all the time, which is good, maybe," mutters a barfly called April White through the alcoholic mists that enfold her like a cocoon. In the best performance I've yet seen her give, Mary Ellen Nester smiles sweetly, blinks her eyes fuzzily and inserts a perfectly calibrated pause between "good" and "maybe." As a result, what could have been just another drunken interjection registers like a pronouncement from one of the great philosophers. Not that April, perpetually blasted, is aware of her achievement.

Or consider this burst of outrage from Savage, who is feeling so boxed-in this evening that she tries to appropriate the lover of one of her girlfriends, momentarily considers jumping off a cliff and, finally in her desperation, proposes a game of pool. "What was my crime I got life?" she barks, frustration scraping her vocal cords raw. In pool, at least, an action produces a reaction. Life doesn't seem to work that way.

If you hope to bring reason and order to these splintered souls, Shanley's play, directed by Todd London in an environmental setting that makes everyone a customer in the bar, will strike you as a puzzlement or a put-on. The characters are self-centered, confused and grammatically hopeless. And their quest for salvation produces mostly a huge snarl.

Consider: One of the bar's denizens, a shrewd tart named Linda Rotunda, has just lost her boyfriend, Tony Aronica, a stud who has decreed that from now on he only wants to go to bed with "ugly women." Since Linda's main tools for getting ahead have always been sex and makeup, she is thrown off her high heels by his decision, and her thick mascara can't hide the panic in her eyes. Furthermore, Savage, moving swiftly into the void, has decided to see if she can't tempt Tony with her virginity -- not that she intends to relinquish it. But, she reasons, living with a virgin would be a change for him, and change is a top priority in her value system. Before long, we are in the midst of a raging cat fight and the vernacular is flying.

Realistically, I suppose, this is fairly preposterous. But if you shift your angle of vision slightly and look upon the bar as a metaphorical way station and the spatting as a rowdy search for the answer to life's riddle, the play has a decided originality. You might call it a brawling Bronx spinoff of "No Exit." Flail as they may, checkmate is all these creatures can aspire to. Checkmate and maybe madness in a few more years.

April is already there. Periodically, she "goes Christmas." That is to say, she drifts off into a childlike world of Christmas carols from which only the bartender, disguising himself as a forgiving Santa Claus, can retrieve her. That, too, sounds preposterous in the telling, but as Nester and Grover Gardner play the moment, it is immensely touching.

I have my quibbles with London's staging, which by propelling the characters to all four corners of the Woolly Mammoth's summer quarters at the Washington Project for the Arts tends to tear holes in the play's unusual fabric. More than the others, Cassidy's performance suffers the consequences.

Cassidy is razor-sharp when it comes to a sense of finger-snapping combativeness, suggesting the chip on the shoulder, firing off the lippy retorts. But the character's soft underbelly is less readily apparent and London's direction doesn't allow us many opportunities to see it. Some potential poignance is getting overlooked here.

Jennifer Mendenhall, however, is triumphantly vulgar, as the brassy floozy with the cinched-in waist and a heart of, well, brass. And Howard Shalwitz, with the assistance of a luxuriant wig, plays her wandering stud with the proper mixture of swagger and befuddlement. If they patch up their differences and go off into the night, there are no sunsets here -- only the dying light of day that filters through the grimy windows at the WPA.

Meanwhile, Savage ends up as she began -- "sealed up like a jug of wine been lying in the ocean since the Romans." She has time to kill and time is killing her. The long wait has only just begun.

Savage in Limbo, by John Patrick Shanley. Directed by Todd London. Set and lighting, Lewis Folden; costumes, Peter J. Zakutansky; sound, Ric Cooper. With Grover Gardner, Mary Ellen Nester, Grainne Cassidy, Jennifer Mendenhall, Howard Shalwitz. Produced by the Woolly Mammoth Theatre at the Washington Project for the Arts. In repertory with "National Defense" through Aug. 30.