Unidentified Human Remains and the True Nature of Love involves two lifelong best-friend guys - one gay, one not, played wonderfully by David Blatt and Allen Radway - and a female roommate who's sexually curious, plus a lesbian at the gym, a teenage guy who just wants to be friends but may be willing to be more, and a psychic woman who's a sexually centered shaman.

So just about everyone's in for some form of - you guessed it. And not always sure just what form.

Into all this comes the news that young women are being found bashed and murdered in Edmonton, the Alberta town where the play is set. What does it mean that a character arrives covered in blood and explains he's been "in a fight" at the bar?

I haven't given anything away - from the get-go, we understand that among these bed-divers, who often seem merely confused about themselves or distressed in their own skins, is a real sicko.

Fraser's play - which New City Stage enacts with a perfect intensity that pulls you in even as the script telegraphs itself punch by punch - is both erotic and tawdry, gratuitous to a fault (simulated, or about to be simulated ... everything, people ripping off clothes), and intriguing in its constant action. Scenes fly by, sometimes in a mere five seconds, more like a screenplay than theater.

Maybe the setting of Edmonton - not exactly a North American hot spot - gives Unidentified Human Remains a dated feel when the subject is sexual openness. But it's more likely that in the years since it was written, the sexual angst it conjures has subsided, at least a little.

Or maybe the feeling I got, that this maze of discomfit wasn't altogether well-constructed, came from the playwriting. The worst piece links the killing of women to repressed homosexuality - enough to make you cringe had you not previously balked at a character's unexplained switch to instant dorkhood when his roommate needs some privacy.

But you may have already wondered at the sort of writing that has characters mention, out of nowhere, that another woman has been found dead in the woods.

I was willing to live along these fault lines because director Ryder Thornton smartly created the unsettling feeling that things might explode at any time. Plus, the cast was fully game: In addition to Blatt and Radway, it comprises Ginger Dayle, the head of New City Stage, and Kevin Meehan, Russ Widdall, Kirsten Quinn, and Amanda Schoonover.

It's intimately staged in Dirk Durossette's apartment design with sheer screens, and with Bill Richardson's lighting and Mark Jesse Swanson's sound. Unidentified human remains are, by their nature, puzzling; for other reasons, Unidentified Human Remains is, too. The production is not.

Unidentified Human Remains and the True Nature of Love

Presented by New City Stage at the Adrienne Theatre, 2030 Sansom St., through Oct.18. Tickets: $20-$22.

Information: 215-563-7500 or www.newcitystage.org.