In past seasons, Larry David tried to sell a comedy to ABC, opened a restaurant with Ted Danson and played a lead role in "The Producers" on Broadway.

Now, the fictionalized version of Seinfeld's co-creator thinks he may have been adopted, as HBO's "Curb Your Enthusiasm" returns tomorrow after an 18-month break. Check TV listings for starting times.

"People have often wondered how they'd feel if they were adopted," David says. "I think it's funny."

More than that, the season-long story arc provides ample room for his alter ego to say out loud what social custom forbids, and invite the wrath of nearly everyone around him as a result.

But don't confuse "Larry" with Larry, who inspired Seinfeld's George Costanza and earned a fortune Forbes estimates at $242 million from NBC's hit comedy.

"None of us are like our characters at all," insists Susie Essman, who plays the foul-mouthed wife of Larry's pal and is often asked to curse at fans.

"I aspire to be like that character," says David. "He's honest. It's the things I'm thinking but not saying."

After playing the prickly, tactless TV Larry for so long, the real Larry says he's more apt to speak up about "little things" in everyday life. The two Larrys share other quirks: The real one declined an invitation to promote Curb on :The Tonight Show."

"It's awkward enough having lunch with someone you know in a restaurant, much less having a conversation with someone in front of 5 million people," he says. "Social experiences are fraught with discomfort."

But "if he was really like that character, he'd never be able to do the show," Essman says. He'd be too busy obsessing over petty injustices — including a racist dog, an unappetizing sandwich named in his honor, or the need to buy a brassiere for his bosomy housekeeper, all subjects of early episodes. (They're invented except for the racist dog, who barked only at a black employee in David's office.)

Curb starts with very detailed story outlines, and the entire season is written before any of it is filmed. But unlike most shows, nearly all the dialogue is improvised on the set. "There's a sense of spontaneity, and no emphasis on jokes in this show," David says. "People generally talk the way they talk in life if you were in this particular situation."