Michael Jackson was into men, not boys - and masqueraded as a woman with his lovers, a new book claims.
That's the most sensational nugget in "Unmasked: The Final Years of Michael Jackson," a tell-all by celebrity biographer Ian Halperin obtained by In Touch magazine.

"Michael would dress up as a woman," Halperin wrote of the trysts.
He said the star once picked up a construction worker in Las Vegas and swore him to secrecy.

"The lover admitted Michael made him sign a confidentiality agreement," the book states.
Halperin's book, which hits stores as the world still reels from Jackson's death, asserts that ex-wife Lisa Marie Presley and galpals like Brooke Shields and Tatum O'Neal were his beards.

Jackson never had sex with second wife Debbie Rowe, so "none of Jackson's three kids are his biological children," an "insider" told the author.

Halperin also contends that Jackson is no pedophile and may be a blackmail victim. He claims to have documents proving Jackson's nervous insurance company forced him to pay millions to a teen who accused the singer of molesting him.

Jackson "collapsed in hysterics when he found out he had to do that," the "insider" told Halperin.