Shirley Jones' new book reveals sexy details

To the world she will probably always be "Mrs. Partridge," but Shirley Jones new book paints a very different portrait of the actress.

"Shirley Jones: A Memoir" details her tumultuous relationship with actor Jack Cassidy which included affairs for both of them, her relationship with stepson and co-star David Cassidy and her early days in Hollywood.

Fans of the squeaky clean matriarch of "The Partridge Family" will probably be surprised by several of the details – including a menage a trios between her, husband Jack Cassidy and a young female dancer.

"I am nowhere near as breezy and uncomplicated as Mrs. Partridge," Jones writes. "And I'm not a spoiled Hollywood movie star or a jaded TV icon, either."

Jones, who won the Academy Award for best supporting actress in 1960 for her role in "Elmer Gantry," documents everything from her early stage career to her encounters with movie stars like Marlon Brando and Frank Sinatra. The book goes on sale today.