Anita Pallenberg Finally Tells Her Story in New Doc: Her Kids Reveal How a Secret Manuscript Made It Happen (Exclusive)

When Marlon Richards pitched his documentary idea to filmmakers Alexis Bloom and Svetlana Zill, he got them onboard by saying, “Everybody always talks about my dad; Actually, my mom was the really interesting one.”

Given that the 54-year-old English graphic designer is the son of Rolling Stone Keith Richards and model Anita Pallenberg, it’s no surprise the directors were hooked. “We love stories about strong women that historical narratives have overlooked,” Bloom says.    

The result is Catching Fire: The Story of Anita Pallenberg, which features interviews with her inner circle, including Keith and their children Marlon and Angela, and friends Kate Moss and Marianne Faithful.

Scarlett Johansson narrates the late model’s words against a backdrop of rare family photos and home movies taken when the Barbarella actress was raising kids and leaving a cultural imprint, while struggling with addiction.  

It was more than two years after Pallenberg’s 2017 death at 75 that Marlon and his kids discovered her secret manuscript while clearing her London home.

“My mother was a massive hoarder. She had this small flat in Chelsea and it was packed to the gills with stuff,” the father of three says. Speaking to PEOPLE exclusively, he adds, “She was quite good at hiding things, almost like a treasure hunt.”

His daughter Ella discovered the book manuscript. His son Orson found the shoebox of 13 tapes, interviews about her life that the Italian German secretly recorded in New York in the 1990s. “I had to sit down and have a bottle of wine,” Marlon says about reading his mom’s account of her life. “It was revelatory. She said things I had no idea about.”

It was a “shock,” he says, but not surprising that his witty mother who never looked back would secretly write her memoir.

Born in Europe amid the bombs of World War II, Pallenberg was 19 when she moved to New York in 1963 to become a model. She partied with Andy Warhol and poet Allen Ginsberg, but it was in Munich, Germany in 1965 that she met the Rolling Stones backstage after a concert. At first it was founding member Brian Jones who captivated her.

“He was the most beautiful one in the group and he had striking intelligence,” Pallenberg said.

But they broke up in 1967 when, fueled by his rages, their relationship descended into domestic violence, and she fell in love with Keith. “It was a good time in my life,” Pallenberg said of the early days of their romance. “Keith was still shy... I brought him out with my Italian energy.”    

Keith, now 80, says in Catching Fire that he was “bursting in love” with Pallenberg. Her influence on him and the Stones ran deep. When he started wearing her clothes, he says he was “considered… to be the best dressed man in the world.” “She had an amazing eye,” he notes.

To this day the Stones — who are currently touring the U.S. — perform songs inspired by Pallenberg. After watching his girlfriend and Mick Jagger get close while playing lovers in the film Performance, a wounded Keith wrote 1969’s “Gimme Shelter.” “You Can’t Always Get What You Want” was inspired, Pallenberg said, by Jagger’s “half-hearted flirtations” when the three were on a trip to Peru. She was pregnant with Marlon at the time.

Keith wrote “You Got the Silver” as a tribute to her after their son was born in August 1969. But the rock star didn’t want the new mom to work, and Pallenberg numbed her pain with heroin.

By the time the Stones recorded their 1972 album Exile on Main St. at a chateau in France, the couple regularly used hard drugs.

Marlon was a toddler running around when the band recorded classics like “Tumbling Dice” late into the night, while hangers-on wandered in and out, gawping at Keith when he passed out.

“It was an absolute nightmare for her because she was running this house fundamentally with 35 to 40 people there every day working,” he says. “They created a wonderful album but, without her matron-like status, I don’t think it would have gotten done as well.”

Facing arrest for their drug use, the U.K. tax exiles hastily left France; the family’s frequent moves became a constant in young Marlon’s life. In Catching Fire, he says they moved 20 times in three years because of their “shambolic and hectic" lifestyle.

His earliest memories, though, are happy ones during a period of domesticity in Switzerland where his sister, Dandelion Angela, was born in April 1972. “My mother held up my sister in this [hospital] window to me and then [my dad and I] went off and had some fondue,” he says.

Marlon didn’t know his parents were famous, but their drug use was no secret and the constant fear that they’d be arrested, or overdose was 'trauma-inducing.' 'I recall being quite terrified of them not waking up, because I was aware of people doing that,' he says.

Grief ripped the family apart in 1976 when Marlon’s baby brother Tara died of crib death at 10 weeks old. “I was heartbroken,” Pallenberg said. “Keith never blamed me… but I blamed myself.” Nearly 50 years later, the Richards family still struggle to talk about their loss. Keith took 4-year-old Angela to live with his mom Doris in England. (“Given the circumstances, it was the only decision,” he said.)

“I didn’t see a lot of [Mum] after that, because my nan kept me very guarded,” Angela, 52, tells PEOPLE in a rare interview. “So, I had a very distant relationship for a few years.”

While Angela went to school in Keith’s English hometown, mother and son moved to South Salem, New York, where another tragedy haunted them. On July 20, 1979, Marlon was watching TV when Pallenberg’s friend Scott Cantrell accidentally shot himself in the head. The 17-year-old was mimicking the Russian roulette scene while watching the movie Deer Hunter in her bedroom.

“I heard this gun blast upstairs and my mother came down screaming,” Marlon says. “She was in shock, in tears and covered in blood.” Knowing that the police were on their way, the 10-year-old did what he’d been “taught” to do; clean up “whatever was lying around, in this case… a gun.” “By then I was a seasoned pro, a bit like the Harvey Keitel role in Pulp Fiction," he adds.

“The only way to deal with it is in a matter-of-fact manner,” Marlon says, reflecting on how he tells the story, without drama. “If you try to get too emotional about it, it’s too much.”

“All I heard was the click of a gun,” Pallenberg later recalled. “It was someone’s life, and I had my back turned. I felt like some nasty person who caused death and destruction around her.” The triumph of Catching Fire and her life is that, after failing to find solace in drugs and alcohol, she decided to get clean.

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After splitting with Keith (who later married model Patti Hansen, with whom he has two daughters) Pallenberg went to rehab, then studied fashion textile design at art college in her 40s. In later life she returned to acting and modeling, becoming fast friends with Moss, who proudly copies her bohemian style.

Angela, who lives 10 minutes away from her brother in Sussex, England, believes Catching Fire hits “every emotion” and “beautifully” reflects her mom’s “charisma.”

Marlon thinks Pallenberg would “secretly like” it too. He says, “She wanted her story to be told. She realized that coming from her it would be a vanity project and she just didn’t want to revisit the past. She left it for us to do that.”

Catching Fire: The Story of Anita Pallenberg will be released in theaters on Friday, May 3.