It's not working, I'm calling it off, I'm walking out the door. This is the persistent temptation of Penny Golden, the emotionally needy waitress and photography model in D.C. playwright Allyson Currin's two-character comedy, "The Subject." The audience is likely to empathize, and not just because the scruffy-but-handsome photographer for whom Penny is sitting has an offbeat appeal that frequently slides over the line into creepiness.

It's because the script itself vacillates between lovable and leavable.

"I have a stalker!" Penny screams a minute or so into the show, a premiere by Charter Theatre in the tiny confines of the Warehouse Next Door on Seventh Street NW.

"I prefer the word 'soul mate,' " replies David, the stalker/photographer. As delivered by actor Chris Stezin, that answer is gentle, humorous and accompanied by the demented gaze of a deranged war vet. With that, the potential lovebirds have met cute.

Swallow Currin's tenuous setup and you're in for an Act 1 of Penny modeling on a secondhand chaise in David's shabby little studio, gabbing merrily while David pleads for quiet and obsessively scrutinizes her left foot with his camera. (David, we learn, is a man who has taken nearly 3,000 pictures of his grandmother's quilt; Penny is his new subject.) Currin taps into Penny's rich chatterbox vein and lets the daffy dialogue flow, revealing a character who is fizzy and fuzzy in equal degrees.

Kathleen Coons is very good at blending Penny's nutty energy and heavily cloaked loneliness, but the conversation is about as one-sided as it can be: "You are constant white noise," David complains in one of his rare lines. So it's not long before you wonder how Currin can possibly tease this wan little scenario into a full-bodied play.

She pulls it off in part through the gradual accretion of character details -- standoffish David's focus on isolated bits and his unsettling, psychologically revealing "no fingerprints" policy; insecure Penny's penchant for making lists and carrying three bags. Currin's opposites eventually erupt in a heated battle that climaxes in a spontaneous photo shoot. As the camera clicks and Penny finally drops her guard, Coons delivers a particularly divine 90 seconds of acting.

The air goes out of the ball again in Act 2 after a betrayal that just about gets talked to death, and much of the trouble is David. (Perhaps it's no surprise that Currin, who is also a reliable comic actress, has more fully realized the part she could play.) The playwright wants to keep you guessing, as Penny does, whether this guy is about to become a big somebody or is just a nobody. Stezin has trouble filling in the vast empty patches. In Stezin's performance, the wild eye comes and goes, and most of the rest is a big blank.

Currin's writing, as usual, has a certain lift and shine. She likes to entertain (no crime there), and she's generally smart enough to avoid coming across as fatuous or glib. Director Richard Washer gives "The Subject" the few production elements it absolutely calls for -- David's chintzy studio and his mysteriously off-limits cabinets -- and Currin sees her premise through to a surprisingly nifty ending.

At its best, the script is glossy enough that you can't help picturing what a theater with means might make of it if a clever designer filled the background with ever-changing blowups of the strange and reportedly beautiful photographs the characters create. But that's another subject.

The Subject, by Allyson Currin. Directed by Richard Washer. Production design, Thom Seymour, Keith Bridges and Chris Stezin. Approximately 110 minutes. Through Oct. 17 at the Warehouse Next Door, 1021 Seventh Street NW. Call 202-333-7009 or visit www.chartertheatre.org

Kathleen Coons and Chris Stezin, as a model and photographer, have an uneasy relationship in Allyson Currin's "The Subject," at Charter Theatre. Kathleen Coons and Chris Stezin in "The Subject," a two-character work by D.C. playwright Allyson Currin.