“I’ve kept silent all these years because I didn’t want to hurt any of these people,” Mr. Bowers said recently over lemonade on his patio in the Hollywood Hills, where he lives in a cluttered bungalow with his wife of 27 years, Lois. “And I never saw the fascination. So they liked sex how they liked it. Who cares?”

He paused for a moment to scratch his collie, Baby, behind the ears. “I don’t need the money,” he continued. “I finally said yes because I’m not getting any younger and all of my famous tricks are dead by now. The truth can’t hurt them anymore.”

Twenty-six years after Hudson’s death from AIDS and more than four decades after “Hollywood Babylon” was first published, it will come as a surprise to no one that the images the movie factories created for stars of the 1940s, ’50s and ’60s — when Mr. Bowers was most active — were just that: images. The people who fed the world strait-laced cinema like “The Philadelphia Story” and perfect-family television like “I Love Lucy” were often quite the opposite of prudish in private.

At the same time, a lot of what Mr. Bowers has to say is pretty shocking. He claims, for instance, to have set Hepburn up with “over 150 different women.” Other stories in the 286-page memoir involve Spencer Tracy, Cole Porter, the Duke and Duchess of Windsor and socialites like the publisher Alfred A. Knopf. “If you believe him, and I do, he’s like the Kinsey Reports live and in living color,” said Mr. Tyrnauer, who recently completed a deal to make a documentary about Mr. Bowers.