The book Warrior: Audrey Hepburn that I wrote in close collaboration with Luca Dotti, Audrey’s son, will be released September 28. It tells the story of a side of her that’s been touched on in other biographies but never explored. And it’s a common human theme, particularly among women: “I left the workforce to raise my children and now they’re grown. What do I do next?”

Audrey Hepburn found Audrey Hepburn a tough act to follow. An impossible act to follow. As an ingenue she had won a Best Actress Academy Award and been nominated four other times. She had won three British Film Academy Best British Actress awards and her mantel also held Golden Globes, New York Film Critics Circle Awards, and on and on. She had conquered Broadway and won a Tony and as a sidelight became the world’s most important clothes horse. Even after she was long retired, publishers hounded her to write a memoir.

At age 57, with older son Sean working in L.A. and younger son Luca on his own in Italy, Audrey stood at this important and vexing crossroads in frustration. She may still possess some vestige of the face that had launched a thousand magazines, and some sense of the talent that had earned her all those honors, but film roles for women in her age bracket were in 1986 what they are today: scarce. She had dutifully kept the same agent into the 1980s that had represented her in the Sabrina days, Kurt Frings, and he reviewed script after script and sent many on and always Audrey reviewed them with disappointment. Too violent, too depressing, too gory, too vulgar.

But despite her chronological age, she knew she was still young. Inside she felt the same exuberance that had gotten her through two shows a night dancing in West End choruses 35 years earlier. She ate healthily and loved long walks in the Swiss countryside. She traveled often—one week would find her in Paris and the next in Hollywood.

Staying in film was the obvious answer. She had never loved film work and yet films had earned her a nice living and it’s what she knew, so she kept looking at the scripts and even threw her hat in the ring for the role of a society matron in a television miniseries, The Two Mrs. Grenvilles, and it was here she learned the latest of life’s lessons: When you jump into such a casting pool as this, you better be ready for sharks. Not only did Academy Award-winner Claudette Colbert want that part; so did Academy Award-winner Bette Davis, and Colbert got it and would earn an Emmy nomination.

Funny thing about Audrey Hepburn: She had an ego that resulted inevitably from decades of success and an inferiority complex several times wider. Fame bewildered her because she didn’t consider herself pretty enough or talented enough to have earned it. All she could say with certainty and a lot of pride was that she worked damn hard and gave herself with total commitment to any job she took on. She had to work twice as hard as everybody else because she was, in her mind, only half as good an actress.

So what about that memoir? She probably could have commanded a million-dollar advance but no way would she ever do such a thing. Because of the war she had some skeletons in the family closet that she must keep locked away. More than that, editors would expect the inside story on her life and career and that meant dishing about friends and co-workers. She may have known that Humphrey Bogart was a bitter man who had no patience for her on the set of Sabrina, but that was her business, just like her affair with co-star William Holden on the same picture was her business. She would never dream of sharing these matters with the world.

The life she was living in retirement wasn’t exactly torture. She owned a Swiss farmhouse tended by a wonderful staff. She maintained a world-class fruit and vegetable garden that provided bounty for the table almost year-round. She had minded her money to the extent that she could provide for herself and her family. And she had finally at long last found the love of her life, former actor Robert Wolders. She could easily live out her years at home, or visiting family, honoring famous friends, endorsing the occasional product, and presenting at the Oscars.

But that was just it—Audrey Hepburn had never done things the easy way, so why start now? And that is the jumping-off point for Warrior. Other authors always treated this as just another chapter in the story of her life. The final chapter. To me, it’s the beginning of an epic adventure.

Pre-order the 368-page GoodKnight Books hardcover Warrior: Audrey Hepburn now.