By Wendy Rosenfield

for the Inquirer

Christopher Durang has many fans, not least of whom granted his Vanya and Sonia and Masha and Spike a Tony Award for best play in 2013. A longtime resident of Bucks County, he's also a mainstay around these parts. Princeton's McCarter Theatre premiered the comedy in 2012, and with this production, Philadelphia Theatre Company continues its long association with him.

At its best, Durang's satirical vision is sharp, merciless, and hilarious. At its worst, he aims low at easy targets. This play, frustratingly, exhibits both tendencies, but PTC's production, directed by James J. Christy, hits bull's–eyes all around.

A Chekhovian grab-bag set in a country house somewhere between Dorothy Parker's old haunt and the town of Upper Black Eddy, David Gordon's set brings the best-loved elements of a disappearing upper Bucks: exposed beams, windowsills deep enough to hold a samovar, bluestone exterior. Inside, Vanya (Kraig Swartz) and Sonia (Deirdre Madigan), siblings - the former gay, the latter adopted - mourn an adulthood spent caring for ill parents, while another sibling, slasher-film queen Masha, galavants around the globe, collecting husbands.

So it goes, until Masha (Grace Gonglewski), whose star is fading fast, arrives with Spike, a glossy boy toy (Alec Shaw), and plans to sell the estate, cherry trees and all.

If Durang remained here, at his best, this would be enough. Gonglewski exercises her comic chops and gets her Gloria Swanson on, while Swartz mopes and fades into the furniture - particularly in the presence of the chiseled Shaw - and Madigan careers through Chekhov's bipolar spectrum until settling comfortably, satisfyingly, on its fulcrum.

Instead, Durang adds a nymphette-next-door named Nina (Clare O'Malley) - that's The Seagull's ingenue - and in one of the play's most egregious missteps, Cassandra (Kianne Muschett), a Magical Negress and voodoo doll-poking housekeeper.

Much like her namesake, Cassandra delivers ominous portents relevant and irrelevant, such as, "Beware of chicken with salmonella," and also reluctantly serves lunch, but with a side of sass. Muschett shines, wringing humor from an uncomfortable role, but if I'm being kind, its inclusion in this play is baffling. If I'm being unkind, it's an embarrassment to the theater-producing and awarding establishment. Or at least it should be.

Vanya also launches into a misguided monologue longing for the good old days of stamps that required licking, shared cultural memories (at a time when sharing was easiest), and television shows that weren't "worthless" (at a time when television writing was at a zenith). It's a sad and poignant bit that Swartz handles achingly well, but even more, it's an indication that Durang doesn't need a fortune-telling voodoo housekeeper to tell him his own best days may be past.

Presented by Philadelphia Theatre Company at the Suzanne Roberts Theatre, Broad and Lombard Streets, through April 30.
Tickets: $25-$59. 215-985-0420 or www.PhiladelphiaTheatreCompany.org.