"Killer Joe" is what might have happened if, say, Shakespeare had been writing down in the Central Valley, around Parleir or Earlimart, in the '90s. It certainly contains as much bawd, blood and bodies as anything the Bard ever did.

The Tracy Letts play that opened Saturday at the Magic Theater in San Francisco, following a successful run at Marin Theatre Company, is completely devoid of any social consciousness: It makes merciless fun of classic American trailer trash and is almost entirely politically incorrect when it comes to matters of morality, sexual abuse and violation of many of the major statutes in the penal code. The show also contains nudity, which, at once, elevates the idea of gratuity to new heights while offering a shocking shorthand commentary on both sexual abuse and casual sexuality.

"Ain't nothing you haven't seen before," stepmother Sharla Smith (Stacy Ross) says to her stepson, Chris (Ryan Montgomery), when he complains about her answering the door naked from the waist down.

That's how the story of the Smith family begins, with Chris pounding at the door in the middle of the night, waking not only Sharla, but his pop, Ansel (Howard Swain), and innocent-beyond-belief little sister, Dottie (Anna Bullard), with the news that his real mother has kicked him out, and he needs six grand right away or his drug connection will kill him.

But Chris, who, like the rest of the family, probably doesn't own a 401(k) or a single mutual fund, does not come to the family trailer without a plan. It seems real mother has an insurance policy that will pay $50,000 should she, God forbid, happen to die. And young Chris just may have a way to pull that off.

He's heard of a man named Killer Joe (Cully Fredricksen), a genuine police detective who moonlights as a hired killer.

So, he says (and this probably sounds better if you've consumed a half-dozen or so Budweisers), the Smith family could hire him, have enough money to live happily ever after on the sort of easy street people with dry, dead weeds in their herb garden envision, and have money left over to pay the $20,000 hitman fee.

Killer Joe, however, is a strictly cash-in-advance kind of middle-aged guy, so he sees no way that he can do the job -- until, he spots tiny Dottie, all virginal and 20 years old. He will take the job if the family agrees to provide him with Dottie as sexual collateral.

Who would imagine a hardened tough guy would fall for a sweet, innocent little gal like Dottie. Oh, wait ... that quickly becomes clear, too.

This, as you may have gathered, is not a play for everyone, but if you enjoy something a bit different and more than a bit profane, violent and overtly sexual, "Killer Joe," may be a highlight of the theater season for you.

On the other hand, if you are easily offended, "Killer Joe" will rapidly press all your buttons.

Saturday's opening was not without flaws; at times the actors seemed to switch on some sort of automatic pilot, making road kill of portions of "Killer Joe." Occasionally, the otherwise stunning cast in the dark and chilling tragicomedy seemed to step off the razor's-edge, roller-coaster ride demanded by the script, and sort of drift for just a tiny bit. But even a few seconds is enough for a minor derailment and a jarring flaw that, in truth, is hard to forgive with a play and cast of this quality.

Certainly, all the performances, along with Lee Sankowich's direction that manages to wring both the comedy and tragedy equally out of the story, are incredible. It's the sort of show, albeit nearly a decade past its off-Broadway run and arriving in the Bay Area for the first time, that sets theater in a new and dark direction, and offers actors a chance to delve into emotional territory that requires both a deft comic touch and a flair for profound tragedy.

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