But in the case of "Intimate Exchanges" - which stars 1812 Productions doyenne Jen Childs - it's really the "how" and not the "what" that makes it unique.
According to Carpenter, "Every show begins with the same first scene, and each scene has a different title. The first scene is called, 'A Gardner Calls.' At the end of that scene, a character makes a decision, which sends the play in one of two directions . . . depending on what the audience chooses.
"For example," she explained, "does [a female character] decide to go out with [a male character], yes or no? Then a light will appear on a random member of the audience, and [he or she] will make that decision. And then the stage manager will announce, 'We're going in that direction.' "
To make this strategy work, noted Carpenter, the actors have to learn about 200 pages of dialogue comprising 16 scenes - some of which, she added, may never be performed, depending on how audience members vote.
Not surprisingly, the play - which is part of this year's FringeArts Festival - holds challenges for the director as well as the actors.
"It's been fascinating," Carpenter said. "The biggest challenge has been coming up with the idea of how the audience is going to choose, and that's still the big mystery.
"To me, it all hinges on that first scene as the possibility for every potential outcome, [so it depends on] how the characters present themselves in that first scene. It's very much based on character interaction, their specific characteristics and the relationships they have with each other."
This, she continued, makes the piece "very similar to life. Sometimes you're given seemingly mundane choices: 'I don't think I'll go for a walk with you,' or 'No, I don't think I'll go out with you Friday night,' or, 'I will go out with you Friday night.' Those seemingly in-the-moment, mundane choices wind up having big ripple effects down the line we can't anticipate.
"And underneath those choices are history, context, in-the-moment chemistry. It's really interesting to figure out each scene: If we play it too heavy on this side, then this choice won't seem to make sense to present the audience with. So we have to make every choice possible. There's a lot of subtlety involved."
The play's blueprint seems to require the director to give up a good deal of control that usually comes with the title. After all, it's the audience members who ultimately determine how things proceed.
"In the traditional sense, you give up a certain amount of control," she reasoned. "But in a certain sense, I've had to have more command of the material in a play like this, because you have to know the play completely in terms of, this scene is its own unit, and if [the play] goes in this direction, then we have to understand what we have to do to get there."
Although "Intimate Exchanges," which runs through Sept. 21, is entirely scripted, Carpenter likened it to improvisational comedy.
"It's that level of fluidity and unpredictability I find very exciting," she said. "It really could go any way. The actors have to use that excitement, that uncertainty, to kind of fuel how those characters go that night. That to me is very exciting, [as is] the idea of involving the audience in that journey. The entire evening is predicated on a unique collaboration between the audience and performers."
The Arcadia Stage at Arden Theatre Company, 40 N. 2nd Street, show times vary, $26-$40, 215-592-9560, 1812productions.org.