The Plots Thicken : Were the Bradys truly a happy bunch? What was Tina Louise of ‘Gilligan’s Island’<i> really </i> like? In a wave of new books, TV stars of the past share secrets about some of our favorite shows.

“The Brady Bunch’s” Greg Brady went on a date with his mother, Carol, and made out with his sister Marcia. “Star Trek’s” Capt. Kirk did kiss Uhura.

Warped plots from lost episodes? Nope. These are cast members’ real-life accounts of what happened behind the scenes of TV’s most popular reruns.

In the past year, a steady stream of books has made its way to store shelves, quenching couch potatoes’ thirst not only for nostalgia, but to know just what the likes of Thurston Howell III and Alice the maid were like in real life.

Publishers used to buy tell-all autobiographies only of the super-famous. But they have found that baby boomers and twentysomethings are just as or even more interested in tomes from Nick at Night icons.

“Star Trek Memories,” by William Shatner and Chris Kreski, made it to the Publisher’s Weekly bestseller list. Also on bookshelves are “I’m a Believer,” Micky Dolenz’s tales of his years on “The Monkees”; and not one, not two, but three books by “Gilligan’s Island” castaways: Russell Johnson (the Professor), Dawn Wells (Mary Ann) and Bob Denver (Gilligan).

In the works are books from Batman (Adam West) and Robin (Burt Ward), David Cassidy, Mary Tyler Moore, Buddy Ebsen, Dwayne Hickman (“Dobie Gillis”) and George (Goober) Lindsey of “The Andy Griffith Show” and “Hee Haw.”

“There are very few people in America ‘Andy Griffith’ and ‘Hee Haw’ haven’t touched,” Lindsey says. “People kept telling me they always wanted to know all about Goober.”

“Goober in a Nutshell: The AUTObiography of George Lindsey” won’t be tell all, Lindsey says, but the book will include a “very honest” account of his rise from his hometown in Jasper, Ala., to his struggle to cope with instant fame as Mayberry’s mechanic, his drinking problem and an “ego that runs rampant.”

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The rush to snap up rights escalated last year with the unexpected success of “Growing Up Brady,” written by Barry Williams (Greg) and Chris Kreski, MTV’s editorial director. The book was on the New York Times bestseller list for three months.

“At first, (publishers) really didn’t understand the value of a Brady book,” Kreski says. “They were more comfortable with a biography of Merle Oberon. But there’s a whole demographic that is not being served.”

“Growing Up Brady” readers found out that off-screen sparks flew between Williams and Maureen McCormick (Marcia) during the filming of the show’s Hawaiian episodes and that Williams once went on a date with Florence Henderson, who played his mom, Carol Brady.

“There’s a great deal of fascination with this stuff,” says Williams, who is writing a sequel based on the show’s reunion series and TV movies. “I guess when you are used to seeing Greg dealing with Carol in a son-to-mother relationship, the idea that the two would go out kind of shakes the senses. But it’s harmless.”

Many books had been written about “The Brady Bunch” and other TV shows, but “Growing Up Brady” was different, Kreski says.

“The other books were sort of ‘Everything’s nice. Everything’s great,’ ” Kreski says. “This was the first one that went underneath it all, but still in a fun way.”

After the Brady book, Kreski found even greater success teaming with Shatner in writing “Star Trek Memories,” published last fall.

Among other things, Shatner tells of his unhappiness with the show’s creator, Gene Roddenberry, and with the network’s decision not to allow Uhura and Kirk have an on-screen, interracial kiss.

(They did kiss, but the network cut most of it out. “We’d give the illusion of kissing without ever touching lips,” Shatner writes.)

“Sufficient time had gone by, and people who had lived parts of their life working on the show were dying,” Shatner says. “The story had to be told, and now was the time to do it. I attempted to tell the truth about making ‘Star Trek.’ ”

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But “you don’t have to give every detail,” Kreski says. “It doesn’t have to be a ‘Spock-ie Dearest’ or the National Enquirer.”

The same holds true for the latest series of “Gilligan” books.

“I left out a lot of stuff,” says Denver, whose book “Gilligan, Maynard & Me” hit bookstores in December. “I didn’t want it to be all trash. I didn’t want to get nasty. It’s a lighthearted book.”

Johnson, whose “Here on Gilligan’s Isle” was published last summer, included details on the making of the show (Carroll O’Connor tried out for the role of the Skipper).

“We were not out to take an ax to anyone’s neck,” Johnson’s co-writer, Stephen Cox, says. “There were a few stories that some cast members enjoyed a toke now and then. After all, it was the ‘60s. But we just decided to drop it. After all, there would be children reading it.”

So why three books in the same year?

“This has become more than just a TV show,” says Sherwood Schwartz, the show’s creator, who is preparing big-screen versions of both “Gilligan” and “The Brady Bunch.”

“It’s a part of the American idiom. You go to any movie and there’s a reference to it. Or any TV show, there’s a reference to it.”

“People have such fond memories of the show,” says Wells, whose “Mary Ann’s Gilligan’s Island Cookbook” (with 13 coconut cream pie recipes) includes behind-the-scenes anecdotes.

“And the show has been on so long, and there’s a new generation of fans. But we each have our own point of view, and that’s important.”

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Johnson, whose book has sold almost 100,000 copies since it was published in July, has drawn large crowds to book signings in West Hollywood and in Manhattan’s Greenwich Village.

The castaways share a few tales about Tina Louise, who was unhappy with her role as Ginger in a show lambasted by critics. In his book, Denver tells of hearing strange sounds from Louise’s dressing room. She was having sex with her boyfriend, he says, an allegation Louise denies.

Others associated with the show have their stories, too. Schwartz’s book, “Inside Gilligan’s Island,” is due in April.

And there are even more “Star Trek” and “Brady Bunch” stories to tell.

Shatner has a sequel, “Star Trek Movie Memories,” due next year. Nichelle Nichols, who played Uhura, also has a book on the way. Williams is working on his follow-up to “Growing Up Brady.” Even Ann B. Davis, who played Brady maid Alice, has a cookbook in the works that includes her own memories.

“That’s strange,” Kreski says, “because when we talked to her, she said she doesn’t like to cook.”