WELLFLEET — Marisa Smith’s new play may be called “Saving Kitty,” but it’s all about celebrating Kate. Led by Laura Esterman’s bracing performance as Kitty’s “kooky” mother, Kate, this world-premiere production at Wellfleet Harbor Actors Theater delights as it jabs at politics, pretension, and hypocrisy.

On the surface, Smith’s plot is painfully predictable: Kitty (Caitlin Clouthier), an up-and-coming TV journalist, brings her boyfriend home to meet her WASPy New York parents, Kate (Esterman) and Huntley (Richard McElvain), in their elegant Upper East Side apartment. There are even references to the 1967 film “Guess Who’s Coming to Dinner,” but instead of Sidney Poitier, Kitty’s boyfriend Paul (Richard Wayne) is an evangelist from Richmond who has come to New York to open a Christian school.

The plot, however, simply affords Smith an opportunity to create the character of Kate, an idle but intelligent woman whose role is to appear clever at cocktail parties hosted by her husband’s employer, the United Nations. The combination of Esterman’s performance and her character’s ability to make breathtaking logistical leaps from one seemingly random comment to another prompts the audience to lean forward, not because we’re wondering if Kitty will be saved, but because we can’t take our eyes off the inventive Esterman, and we want to see how her Kate manages to win what shapes up to be a battle of wits.

Esterman’s Kate is a force of nature, bending nearly sideways as she lobs an endless assortment of quips, quotes, and politically incorrect comments designed to shake up her would-be son-in-law and reveal his true intentions toward her daughter. We learn that Kate had a career as an actress in soap operas before she married, and her put-upon daughter traces the arc of Kate’s dinnertime performance as moving from monster to weeper and, finally, to victim. But even as Kate bounces from comments about the English monarchy to observations about religious fanatics in Turkey, from naming world capitals to quoting the Bible, we know she is more than a drama queen: She’s a mother determined to protect her daughter from a situation she believes is a disaster in the making.

Although this is a four-character play, director Rand Foerster recognizes that the others are simply small planets orbiting Kate. Still, he gives each of them the space to develop their portrayals: McElvain’s bow-tied, bumptious Huntley; Wayne’s Paul, whose smooth demeanor is shaken by Kate’s scrutiny; and Clouthier’s Kitty, who resembles Kate in ways the daughter is not eager to admit. Wayne and Clouthier also make their relationship feel sincere, even if Smith has us wondering about Kitty’s eagerness to shock her oh-so-secular parents with her newest beau.

Foerster keeps the proceedings spinning around Nicholas Dorr’s gorgeous apartment set, delicately balancing Smith’s sharp satire with moments that allow the characters to display enough humanity to keep them grounded. And rather than simply presenting Kate as a ditzy clown, Esterman allows us to see Kate’s vulnerability, making her a more complex character than expected.