Live from Patchogue, it’s Robert Klein

Though it will be 53 years since he first got the crowd going at Chicago’s fabled Second City comedy club, Robert Klein says he’s “still a secret.”

“Most people haven’t seen me do comedy live,” says the stand-up all-star, who gave HBO its first comedy special in 1975 and has since steadily shared his brash, intelligent humor and considerable acting chops on the big and small screens. On Friday, Long Islanders will get the chance to spend an intimate evening at the Patchogue Theatre for the Performing Arts basking in Klein’s uniquely droll takes on daily life.

The audience will find the self-described “geezer” — Klein turns 76 next month — hasn’t lost any of “the hustle of the Bronx streets and the chutzpah of the Borscht Belt tummlers,” as entertainment writer Richard Zoglin put it, that distinguished him when he first burst onto the scene. “I’m after laughs,” Klein says, “not chuckles or nods.”

Klein, together with his iconoclastic colleagues George Carlin and Richard Pryor, formed a triumvirate of modern stand-up that shaped a generation of comics, including Billy Crystal, Jay Leno and Jerry Seinfeld. While Klein says everyone wants to talk to him about what the old days were like, he admits that comedy has changed. “All boundaries have been loosened. It’s not altogether a bad thing, but it’s overdone — instead of using profanity when it’s apt, like a good novelist would,” says Klein.

The comedian’s longevity can, in part, be credited to his versatility. In addition to more than 100 appearances on the big late-night talk shows, he has had dozens of starring and guest-starring television roles, from “Love, American Style” to “Law and Order” to “The Good Wife.” After Patchogue, Klein will head out to Los Angeles to appear as Debra Messing’s father on “Will and Grace.”

Klein has also garnered accolades for his stage work — a Tony nomination for Neil Simon’s “They’re Playing Our Song” in 1979 and an Outer Critics Circle Award for Wendy Wasserstein’s “The Sisters Rosensweig” in 1993 — as well as two Grammy nominations for his comedy albums. “My LPs became CDs and then MP3s,” he quips. He is also the author of “The Amorous Busboy of Decatur Avenue: A Child of the Fifties Looks Back.”

Klein suspects his Broadway days are over. “I don’t want to show up eight times a week and then not be able to change the lines. Doing stand-up, I can change the words any time I want.” Along with a good dose of improv and big laughs, the Patchogue audience can look forward to Klein’s Emmy-nominated “Colonoscopy” song, a few tunes on the harmonica and perhaps a flash of his signature striped socks.

“When you get me onstage, I feel that’s where I belong. There is a tremendous amount of affection coming over the footlights,” he says. “There’s nothing like a live audience.”