Audrey Hepburn’s Secret Past: New Book Reveals How She Risked Her Life to Fight Against Nazis 

The world fell in love with her doe-eyed beauty and stylish perfection in such films as Breakfast at Tiffany’s and Sabrina, but Audrey Hepburn‘s real-life story was always far more complicated.

“When my mother told us about her life, she never talked about Hollywood or her films,” says her younger son Luca Dotti, 49. “She would tell us stories about the war. And she spoke about good and evil.”

Even as a young boy he says, “I knew from her eyes, her expressions, and her shaky hands that there was more to the story.”

26 years after her death, a new book, Dutch Girl: Audrey Hepburn and World War II, by historian and biographer Robert Matzen, excerpted in this week’s PEOPLE, tells the harrowing tale that Hepburn long kept hidden.

How she barely survived Germany’s five year occupation of Holland, and how she risked her life secretly working for the Dutch Resistance to help fight the Nazis.

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According to Matzen, Hepburn was a young girl of 14 when she was asked to help the Resistance.

“Audrey once said that one of her jobs was ‘running around with food for the pilots,” he notes, referring to the American and British fliers shot down over Holland.

“As a fluent English speaker, she could communicate with the pilots, tell them where to go and who would help them,” he says.

For more about Hepburn, pick up this week’s issue of PEOPLE, on newsstands Friday.

On one occasion, when she saw the German police approaching, Matzen describes how she kept her wits about her and began picking wildflowers as a diversion tactic.

“When the Germans…reached her,” he writes, “she remained silent and sweetly presented her flowers to them. After a check of her identity card, she was allowed to pass.”

Hepburn also was asked to deliver the local Resistance newspaper, a forbidden publication in Nazi occupied Holland. According to Matzen, the star once described having to “step in and deliver our tiny underground newspaper. I stuffed them in my woolen socks in my wooden shoes, got on my bike, and delivered them.”

Hepburn also helped raise money for the Resistance by participating in illegal musical and dance performances, called “black evenings,” due to the windows that were blacked out, says Matzen, “so the Germans would not realize what was going on. Afterwards money was collected and given to the Dutch Underground.”

Of those secret performances, Hepburn once said:”Guards were posted outside to let us know when Germans approached.”

She also added, poignantly: “The best audiences I ever had made not a single sound at the end of the performance.”

The war was personal for her in a way that only her closest loved ones knew. Her beloved uncle, Otto van Limburg Stirum, who was married to her aunt, was taken away and executed by the Nazis when he refused to support the regime in 1942.

She also suffered several malnutrition due to the lack of food, to the point of nearly starving to death.

Her son Luca Dotti, who wrote the forward to Dutch Girl, supports the full story coming out, noting: “It’s a good time to tell my mother’s story and to know her as more than just an icon of beauty and style.”

“There were times reading this book that I was crying,” says Dotti. “I imagine how brave she was, working for the Resistance and also how easily she could have died from lack of food, or from a bomb or a bullet.”

“To imagine my mother in these conditions was a shock,” he says. “You can feel her trauma but also her strength.”

It was that strength that propelled her to travel to war-torn countries as an ambassador for UNICEF in her later years, which she found her true calling.

“My mother always said that there is no greater evil than war because it affects the children.”