After three decades away from the sport, the former marathon swimmer turned broadcaster and journalist had decided to return to this lifelong dream — and when the famously iron-willed Nyad decided to do something, nothing would stand in her way.

Over the past 3½ years, coached by her longtime best friend Bonnie Stoll, Nyad had poured endless amounts of energy and training into trying to complete the swim: 16-hour endurance sessions. Thousands of burpees. Complex logistical planning with a crew of more than 40 people. Her three previous attempts in 2011 and 2012 had failed, derailed at various turns by storms, an asthma attack and box jellyfish stings that nearly killed her. Now, at 64, on what could be her final attempt, she needed everything to go her way.

After swimming from Cuba to Florida, Diana Nyad became a much-in-demand speaker. Here she addresses “Visionary Women present Grit, Guts, and Grace: Lessons in Overcoming Adversity and Cultivating Resilience” in 2017.

(Rachel Murray / Getty Images)

“Every day, we were like, ‘Is there a window? Is there a window?’” Nyad says on a recent morning in an office on Hollywood Boulevard. “Every day, we were sitting with the meteorologists and looking at the Atlantic gyre.”

Completing the 110-mile swim across the Florida Straits was a grueling and dangerous prospect for even the strongest swimmer. Only two people had done it before — 65-year-old Walter Poenisch in 1978 and 22-year-old Susie Maroney in 1997 — both of whom used shark cages (Poenisch had also used a snorkel and fins). Nyad herself had tried and failed in 1978 when she was 29.

Returning to the goal decades later, Nyad, with the same brashly confident flair for seizing the limelight that had first propelled her to stardom as a swimmer and sports commentator, declared her intention to be the first person to make the swim without a shark cage. With each failed attempt, her death- and age-defying endeavor drew more media attention and public support.

Finally, on Sept. 2, 2013, after nearly 53 hours of swimming, Nyad staggered onto Smathers Beach at Key West, face severely swollen and legs barely holding her up. Ringed by a cheering crowd, she hugged Stoll and stepped toward a microphone to deliver a message: “You should never, ever give up. You’re never too old to chase your dreams.” It was like a scene out of an inspirational sports movie.

And now it is one. Led by the powerhouse acting duo of Annette Bening as Nyad and Jodie Foster as Stoll, Netflix’s “Nyad” chronicles the swimmer’s improbable late-in-life effort to fulfill her quest as well as her partnership with Stoll, chief navigator John Bartlett (Rhys Ifans) and the rest of the crew. One of the streamer’s key awards hopefuls this year, the film marks the narrative feature debut of documentary filmmakers Elizabeth Chai Vasarhelyi and Jimmy Chin, who won the best documentary feature Oscar in 2019 for “Free Solo,” about climber Alex Honnold. Oscar prognosticators are already speculating whether Bening, who spent a year training to play the swimmer, could land a fifth Oscar nomination for the film. Foster, who has won twice, also is considered a potential contender.

Diana Nyad starts her fifth attempt to swim across the Florida Strait on Aug. 31, 2013, in Marina Hemingway, La Habana, Cuba.

(Ernesto Mastrascusa / LatinContent via Getty Images)

But just like Nyad when she set off for Key West, the film will face choppy waters on its path to potential glory. In recent months, as the release of “Nyad” has approached, decade-old questions about the way Nyad’s Cuba swim was conducted and documented have resurfaced in the small but impassioned marathon swimming community, along with broader accusations about Nyad’s own character and credibility, complicating the film’s PR rollout.

“Diana is like a Trumpian figure in this space,” says Elaine K. Howley, a marathon swimmer who also has covered the sport as a journalist. “Whether you like her or not, she sucks up all of the oxygen in the room with her boastfulness and exaggeration and narcissism. There are conflicted feelings because finally this really cool, really hard sport we love is getting the feature movie that it deserves — and there are a lot of us who feel, like, really? You’re going to make it about her?”

Days before the film’s Telluride premiere, Nyad sits beside Stoll in the office of her high-powered publicist, Kelly Bush Novak, who also represents tennis star Serena Williams as well as numerous Hollywood luminaries. Nyad and Stoll, 71, a former professional racquetball player, show off their matching tattoos that read ishin-denshin, an East Asian idiom denoting a kind of direct, unspoken understanding. (After a brief early romantic involvement, the two have been friends for four decades.) With the Screen Actors Guild on strike, Nyad, who is a SAG-AFTRA member, was granted approval to be interviewed for this story but was restricted from speaking about the film. “I can only say one quick phrase,” she says. “I was blown away.”

Annette Bening, left, and Jodie Foster play longtime best friends Diana Nyad and Bonnie Stoll in “Nyad.”

(Kimberley French / Netflix)

Within the world of marathon swimming, which has no single governing authority and its own fractious internal politics, Nyad has long been a polarizing figure. (A marathon swim is typically defined as anything over 10 kilometers, or 6.2 miles; roughly 4,000 people worldwide have completed such an endurance swim so far this year.) While her fans and supporters laud her as a pioneer and a guiding light, some of her peers have criticized her for what they regard as a history of making overblown claims about her career and, in the case of her most famous achievement, seeming to play by her own rules.

The story of Nyad’s Cuba-to-Florida swim brought her worldwide fame. In its wake, she was invited to President Obama’s White House, did a stint on “Dancing With the Stars,” was interviewed by Oprah Winfrey, gave countless motivational speeches and wrote a bestselling 2015 memoir, “Find a Way,” on which the forthcoming biopic is based.

In the run-up to the fall release of “Nyad,” however, her detractors in the swimming community have been raising objections on social media and in online forums. One former marathon swimmer, Daniel Slosberg, has waged a particularly intense and, at times, bitterly personal campaign to highlight questions about Nyad’s claims through a website he created several years ago, Nyadfactcheck.com.

“Diana Nyad is only a big figure in the marathon swimming community in the sense that she’s loud,” says Slosberg, who has combed through Nyad’s public statements, writings and swimming records stretching back to the 1960s with a zeal bordering on obsession. “Most people in the community are very supportive of other marathon swimmers. But they don’t take Nyad seriously. The main buzz in the community is that this is a travesty.”

In December, the World Open Water Swimming Assn., one of the sport’s two main global organizations, published an exhaustively researched report on Nyad’s 2013 Cuba swim. In a piece published last week on its website titled “‘Nyad’ on Netflix: The Swim, The Scandal, The Silence,” WOWSA noted that Nyad’s swim has never been officially ratified and advised viewers of the film to “watch with discernment, keeping in mind the discrepancies about the swim.”

The Guinness Book of World Records recently removed Nyad’s record for the swim from its database after WOWSA flagged its lack of ratification. (Nyad’s allies are pushing to get the record reinstated.)

Diana Nyad, right, with her friend and coach Bonnie Stoll, photographed at Stoll’s home in Los Angeles on Aug. 25, 2023.

(Allen J. Schaben / Los Angeles Times)

While representatives for the film and Nyad have quietly scrambled behind the scenes to tamp down the blowback, co-directors Vasarhelyi and Chin, who are married, are standing firmly behind “Nyad” and its subject.

“When you are pushing the edges of your sport, you have a target on your back — and, it seems, particularly if you’re an outspoken gay woman in her 60s,” says Chin, who is a professional mountain athlete. “A lot of the athletes that I’ve worked with haven’t been universally loved because they’re dedicated and committed. And sometimes to make things happen, you have to bulldoze through all the barriers. You have to be a force of nature. Diana is a force of nature.”

“Nyad” is hardly hagiography. Even as it celebrates her Cuba swim, the film offers a nuanced depiction of Nyad as charismatic and fearless but also prickly, boastful and prone to self-mythologizing. In one scene, Foster’s Stoll accuses Nyad of having “a superiority complex.” In another, she teases the swimmer for exaggerating a story about a corporate sponsorship deal she once secured.

Vasarhelyi says the film is intended to be both a warts-and-all portrait of Nyad and a celebration of her determination and grit. “Diana Nyad is a complicated and extraordinary human who did something astonishing,” she says. “Self-aggrandizing? I don’t know if we’d say that if we were talking about a man. I think Diana is just not afraid to say what she thinks and talk about what she has done. That is incredibly inspiring, and I want my daughter to see that film.”

Asked about the questions over Nyad’s credibility, Vasarhelyi said, “You see it all in the film. The point is that she is unabashedly a complicated, gray character in real life, and we went to great lengths, as did Annette, to portray that in its full glory. It makes me really sad that we are scrutinizing things that happened 30 years ago and not acknowledging and celebrating the extraordinary achievement. Because I think as a society, we’ve witnessed a lot worse and celebrated a lot worse.”

With “Nyad” slated to hit select theaters Oct. 20 before arriving on streaming on Nov. 3, the film’s subject finds herself caught between a public that is buoyed by her uplifting story and a marathon swimming community that doesn’t fully buy it. Faced with renewed criticism, she is alternately defiant, proud and conciliatory.

“Here we are in Tinseltown,” Nyad says, looking out at a sweeping view of the Hollywood Hills and the downtown L.A. skyline. “Bonnie and I have a number of actor friends and they’ll say to us often, ‘Diana, your type of fame has to do with something real.’ I don’t consider myself famous — I never use that word. I think I have some public respect. Ironically, less from the marathon swimming world than the rest of the world. But that’s my cross to bear. And I hope they come around to me at some point.”

She chooses to focus on the millions of people who have been moved by her story, who have lined up at book signings and speeches to tell her that her example motivated them to undertake some daunting challenge in their lives. “Does it feel good to inspire people?” she says. “Yeah, it does.”