Wholesome former THE Brady Bunch star Maureen McCormick is set to reveal the beloved 70s TV series' most shocking secret in a new book - she and her on-screen sister had a lesbian fling. MCCormick's tell-all, Here's The Story, won't hit bookstores until 2008, but publishers are already buzzing about the big reveal. As well as talking candidly about her well-documented eating disorder and drug problems in the book, TV's Marcia Brady will come clean about a romance she had with co-star Eve Plumb, who played her sister Jan on the hit show. A source tells America's National Enquirer, "The most explosive comments will be how the then-blonde, blue-eyed cutie developed a crush on Eve Plumb, which led to some sexual play. "This book will certainly come as a shocker. While Maureen is not a lesbian, she reveals there were some sexual hijinks going on behind the scenes. "It's bizarre because she played such a virginal character on the show."