Creepy, crawly, terrifying - and excellent

Brace yourself: Theatre Exile's knockout production of Tracy Letts'

Bug

is creepy and compelling and violent and funny and sad: humanity at its most vulnerable and most repulsive and most shocking.

It starts in the standard-issue trashy motel room where Agnes (the superb Grace Gonglewski) lives her "hermeticized," coked-up life. The phone keeps ringing, but when she answers, nobody speaks.

She is afraid of her ex-husband, Jerry Goss (William Zielinski), who is just out of prison, a sleazy, mocking, nasty guy ("Whose fault was it that I hit you?" "Mine"). Her friend, R.C. (Charlotte Northeast), a lesbian biker, tries to bring some order and kindness into the tinderbox of Agnes' life. She also brings a guy, Peter Evans.

Peter (Matt Saunders) is a mild-mannered stranger with an intellectual vocabulary, who seems oddly vacant, making us wonder what that flat affect hides. He soon becomes Agnes' friend and lover.

Then it begins: Peter finds itchy bug bites on his arm. Uh-oh.

And you know how it is with bugs of all kinds, whether they're insects or surveillance devices or diseases: Once you start to itch - or suspect - or fear contagion, there's no stopping.

Peter has been in a military hospital for four years: Is he the victim of obscene, arcane experiments? Is he nuts? Is Dr. Sweet (Joe Canuso) sincere or sinister? The paranoia builds incrementally as Agnes' and Peter's physical and psychological state deteriorates. And because this is such a powerful production, we are swept into the grotesque logic of their growing obsessions.

Agnes' vulnerability - she is guilt-ridden about her son's disappearance years before, and desperately forlorn - leads her into madness. Gonglewski delivers Agnes' terrifying monologue, in which she imagines the elaborate plot against them, with breathtaking plausibility.

Director Matt Pfeiffer shrewdly navigates the fine line between the lurid and the ridiculous, avoiding the script's temptation to turn the play into a gaper delay. There are long, wordless, tension-producing pauses and naturalistic, everybody-talking-at-once scenes. This is brutal theater: lots of visceral, gruesome stuff, totally asexual full nudity, and a conclusion that will make nobody feel good - except with the pleasure of having seen a good play very well performed.

Tracy Letts, who won the Pulitzer Prize for his most recent play,

August: Osage County

, also wrote Theatre Exile's 2006 hit,

Killer Joe

.

Bug

is far less funny, far scarier than either of those plays. As Peter says, "You're never really safe. One time, maybe a long time ago, people were safe, but that's all over." And suddenly, you begin to itch.

Through May 18 at Theatre Exile, Christ Church Neighborhood House, near Second and Market Streets. Tickets $5-$40. Information: 215-922-4462 or

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