Elaine May, the great comedian and screenwriter, once declared that the only topic never to be touched in improvisation was incest. It was her definitive (and correct) opinion that there were no laughs to be derived from the suggestion of sex between siblings, or between parents and children. I’ve been reminded of Ms. May’s strict policy during each of the 10 episodes of “Joey” I’ve suffered through this season, all of which have been digging desperately for comedy in the show’s incestuous premise. I’m not sure what NBC was looking for (besides a quick buck) in putting this messy mix of relatives in the same sexual soup, but the network has ended up with a show almost as creepy as “Fear Factor.”

I chose not to review the show’s wimpy pilot, which fell back on secondhand sex jokes and the intimation of attraction between Joey Tribbiani and his sister, Gina, otherwise played with great gusto and humanity by Drea de Matteo. (At one point in the pilot, Gina commands her brother to cop a feel of her brand-new breasts.) And that’s even though I saw it twice – once with the next-door neighbor played by the pleasantly unrelated Ashley Scott, and again as recast with Andrea Anders, whose painful lack of sex appeal fits perfectly into the show’s misguided premise. I hoped that the writer-producers of “Joey” would eventually discover the gold in their concept: the notion of Joey as mentor to his sister’s grown-up son, allowing a mental growth spurt for a character who’d mined his stupidity for 10 seasons on “Friends.”

Instead “Joey” has kept its focus tight on the side of the Tribbiani character best suited to the cheap laugh – his lack of intelligence and his abundance of sex appeal – and tossed in the sickening aspect of sisterly love. It’s beyond tawdry; it’s nauseating to watch these two grown siblings flirt recklessly with each other, and often in full view of Michael Tribbiani, who has moved in with his uncle to liberate himself from his overprotective mother. This being a sitcom, Mom still spends every waking moment in her brother’s living room, rendering her son’s freedom moot.

When the show isn’t teasing us with the inappropriately cuddly relationship between Gina and Joey, it’s reminding us that she had her son when she was a teenager – hence the fact that they, too, look like brother and sister. In reality, only five years separates Ms. de Matteo and Paulo Costanzo, the actor playing her son – an eternity in a universe where 29-year-old Angelina Jolie can play 28-year-old Colin Farrell’s mother, but mind-numbing nonetheless. There were equally ugly suggestions on later episodes of “Friends,” in which writers desperate to reach the finish line explored the attraction between siblings Ross and Monica. But with “Joey” and a fresh start, we might have hoped for a healthier attitude toward sex and humor.

No such luck. When the writers of “Joey” have to end a scene, they invariably fall back on the same tiresome cliches that defined the Tribbiani character for so long – his relentless (and implausible) stupidity and his jaw-dropping (and equally implausible) magnetism. On “Joey,” beautiful women seem physically incapable of not having sex with him; as it turns out, he’s only a role model for someone aspiring to be a slut. His brainiac nephew wouldn’t mind a piece of Joey’s action, but he can’t seem to get past first base without his mother sticking her breasts into his business. On several occasions she has used her surgically enhanced body to manipulate sexual situations to her son’s advantage; her breasts perform such a regular function on “Joey” that I fully expect them to get their own spinoff series when this show gets canceled.

And it should be. NBC keeps promoting “Joey” as a hit when, in fact, it’s earning only a fraction of the numbers its vastly superior predecessor got, even in its final seasons. With its stale jokes and cringe-worthy setup, “Joey” has no heart or life. Whereas Kelsey Grammer devoted every ounce of his acting powers to keeping his long-running “Frasier” alive, Mr. LeBlanc looks exhausted as he goes through the motions of playing the fool. Imagine how dumb he’ll feel when his feeble new series disappears. And it’s not fair, really – because the real dummies on “Joey” are the writers, who are sending their series to an early grave with their dependence on a decade-old premise that has long since outlived its appeal.

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At 7:33 yesterday morning, all three morning news shows turned their attention to the same breaking news story – a confluence of coverage that would seem more appropriately reserved for events in Iraq or Washington than the celebrity wing of a Los Angeles hospital. I channel-surfed in amazement as “Today,” “Good Morning America,” and “The Early Show” simultaneously interviewed three different People magazine editors about the birth of Phinnaeus and Hazel, the twin babies belonging to Julia Roberts. The most amazing moment: when Charles Gibson on ABC left unchallenged his People Person’s assertion that the world will simply not be able to tolerate Julia Roberts’s absence from movies. They must have been discussing an alternate universe to the one that recently saw “Mona Lisa Smile.”