Actor’s Express is presenting Joshua Harmon’s saucy, provocative, dark comedy “Skintight,” directed by Freddie Ashley, running through Oct. 13.

I will say up front that I found the play well-nigh irresistible. Playwright Harmon enjoys a mutually beneficial relationship with Actor’s Express: His “Bad Jews” (one of the company’s biggest hits ever) and “Significant Other” have played there. He was the company’s Playwright in Residence in 2010. Mr. Ashley speaks of his ability “to seamlessly float between breezy comedy and piercing satire;” that he does in “Skintight.”

Shakespeare wrote, “Sweet are the uses of adversity.” Substitute “beauty” for “adversity,” and you have the major theme of “Skintight.” Blanche DuBois in “A Streetcar Named Desire” said, “Physical beauty is passing; a transitory possession.” It may be, but while it’s around, it can confound, delight, befuddle, or enchant those around it.

Jodi Isaac (Wendy Melkonian), a woman in her “early forties” (as she says), a Los Angeles lawyer, shows up unannounced at her father’s tony West Village townhouse, ostensibly to celebrate his 70th birthday. She’s quite overwrought: Her husband has left her for a twenty-something gym-toned beauty. Her 20-year-old son Benjamin (Jake Berne) will be along shortly.

But Jodi’s father, the formidable Isaac (Chris Kayser), a vastly successful fashion designer à la Calvin Klein or Halston, does not like surprises. He can exude a chilly hauteur, which he turns on his daughter—at first. But there’s something funny about a totally assured sense of entitlement, which Jodi has. Her opening monologue is a caustic, comic masterpiece. But Dad is no pushover.

I must say here that Mr. Ashley’s casting in this play is truly masterful—such that you can’t imagine anyone else playing these roles—and I haven’t even mentioned everyone. There are six.

While Elliot is basically sympathetic to Jodi’s marital woes, he has a teensy little surprise of his own. Namely, a new life partner: a gorgeous 20-year-old man named Trey (Truman Griffin). Trey has a face and body so dreamy that both men and women become disconnected upon seeing him. Of course, you may be immune to Trey’s charms; then again, you may be dead.

“But can he talk intelligently about art?” Harold (in “The Boys in the Band”) would wryly muse. As it happens, he can. He also likes to lounge in the evening wearing nothing but a jockstrap, revealing a dashing derrière. However, there is no total nudity in the play, in case you’re worried.

Back to Jodi: She is at first taken aback with her dad’s new “playmate”; but she balks at the thought that Elliot truly loves him and that they could really be partners. To add to Mr. Harmon’s delicious brew, we find that Jake (her son, remember) is also gay. He has been abroad studying Yiddish and queer studies in Hungary, the Issac family’s ancestral homeland (the Issacs are Jewish; Elliot is from Brooklyn).

And Jake, who’s a trifle nervous and neurotic, is momentarily stunned by Trey, and like all good millennials, takes to his computer and discovers that Trey has been a porn star. Is Trey nonplussed? Not at all: “I wouldn’t call myself a star,” he casually comments. Mr. Berne, a discovery, is spot on.

There are two houses servants, both slyly underplayed: Marianne Fraulo’s Orsolya, who constantly trudges up and down the stairs (fantastic set by Seamus M. Bourne); and the reclusive Jeff (Christopher Repotski), who is a former lover of Elliot’s. He keeps a low profile.

Mr. Griffin contributes a performance of effortless charm; perhaps my favorite moment is Trey’s recalling seeing Michelangelo’s “David.” He speaks with genuine awe at the transcendent beauty, but also notes the crowd’s reaction to the masterpiece. Trey may be uneducated (compared to the others), but he is no dummy.

Of course the playwright is asking a lot of questions about beauty, youth, the nature of familial relations, and cultural implications. But he allows the audience to supply answers. He is becoming a force to be reckoned with in American theatre.

Mr. Kayser’s elegance, poise, and assurance are lovely to behold. His Elliot is magnetic and has a few surprises for us (I haven’t told everything). Many of us have long known what a masterful actor he is.

Ms. Melkonian’s Jodi is superb. She grabs your attention from her first moment and doesn’t let go. Like “Skintight” itself, she is funny, fascinating, maddening, and unforgettable.

If I were you, I would not delay in getting tickets for Actor’s Express’ “Skintight.”

For tickets and information, visit actors-express.com.