The plight of the single girl has almost worn out its welcome.

From the bouncy “Bridget Jones’s Diary” to television’s “Ally McBeal” (R.I.P.), the dating travails of a late 20s/early 30s career woman searching for Mr. Right has been about as topical as superheroes and terrorism.

Heather Juergensen, left, and Jennifer Westfeldt meet in the romantic comedy Kissing

Luckily, there’s still some room to explore within this crowded thematic framework. “Kissing Jessica Stein” manages to function within the conventions of the “Sex and the City” setup, while adding a delicate twist to the proceedings. The result is an engaging “lesbian movie” that plays equally well with male audiences.

Helen Cooper (Heather Juergensen) is a Manhattan art gallery manager who treats sex as a cavalier necessity. She has a stable of different boyfriends to choose from depending on her mood some when she needs intellectual stimulation, others when she just requires a willing stud.

Contemplating one more libidinous realm to enter, the erudite Helen places an ad in The Village Voice looking for female companionship. She approaches the task of finding a lesbian lover with the same gravity as picking a new shade of lipstick.

On the other side of the city, Jessica Stein (Jennifer Westfeldt) verbally spars with her boss and ex-boyfriend Josh (Scott Cohen) at The New York Tribune. Like many perfectionists, Jessica has found a career as a proofreader for a daily paper. It’s a lot easier for her than actually becoming a writer like she had intended to be in college, or indulging in her current passion of painting. Even though she is referred to in the film as a “Jewish Sandra Dee,” she’s more like a female Jerry Seinfeld: overly obsessive about mundane things but charming nonetheless.

During a montage of past dates (most arranged by her concerned mother), she suffers through a predictable lineup of “freaks and morons.” One particular doofus says, “You’re phat with a P-H” before talking about his “self-defecating” demeanor.

It’s no wonder Jessica finds herself continually drawn to a specific Women Seeking Women ad in the weekly paper. It’s not so much because she’s intrigued sexually, but by the way its author quotes a noted German poet.

The two meet. Jessica isn’t really sure why she responded and desperately tries to back out. But when the pair begin to talk, both realize they have much in common … and maybe something more.

Writers Juergensen and Westfeldt adapted “Kissing Jessica Stein” from a comedy sketch they created for the theater (notice how closely their first names mirror those of the characters they play). It’s not surprising that the two seem so perfectly cast, given that they found the rare opportunity to tailor lead roles for themselves.

Westfeldt gives a clinic in comic timing, managing to be frustrating, charismatic and sympathetic at the same time. The duo’s dialogue continually elevates the film (During one blind date with a software executive, Jessica blurts out, “I don’t hate computers, I just think they’re numbing and obscuring our humanity.”), even when the constraints of the project’s budget show through like visible panty lines.

Director Charles Herman-Wurmfeld begins the movie by trying to cop a Woody Allen attitude. The title sequence goes on way too long, and the zany “Bullets Over Broadway” music practically drowns out the dialogue. Thankfully, he quickly learns to move out of the way of the story, allowing the actresses and their lively script to score all the points.

The writers deserve credit for following the arc of the central relationship to its logical conclusion. These final moments give Westfeldt the opportunity to manifest some genuine desperation, proving that comedy is not her only on-camera skill.

The manner in which the story resolves may irk the politically correct crowd, but it seems pointedly plausible to those living in the real world. And it’s just ambiguous enough to suggest that although Jessica and Helen grow in many ways through the relationship, both their lives end up not all that different than before they met.