In Meru, Free Solo and 2021’s The Rescue, Oscar-winning filmmakers Jimmy Chin and Elizabeth Chai Vasarhelyi excelled at drawing body-tightening tension from true-life feats of strength. Visually vertiginous and vigorously stressful, these fascinating documentaries have sturdy footholds on the complexities of everyday motivations and relationships for people most of us just presume are crazy. Beyond that, they convey how the power of human endurance and persistence can bridge even the biggest gaps of nationality, language, culture and bureaucracy.

Now streaming on Netflix, Nyad represents Chin and Chai Vasarhelyi’s first foray into scripted filmmaking. Here’s hoping it’s also their last — or at least that such future efforts endeavor to evolve beyond boring biopic beats, disengaged direction, lazy writing, dodgy computer-assisted effects work and a waste of sturdy performances from Annette Bening (as long-distance swimmer Diana Nyad) and Jodie Foster as her best friend and eventual coach, Bonnie Stoll.

An introductory montage (and closing-credits postscript collage, for that matter) does nothing to discourage the feeling this should have also just been a documentary. Making her name as a long-distance swimmer in the 1970s, Nyad hung up such efforts after a failed attempt to complete a 103-mile unassisted swim from Cuba to Key West. And yet 30 years later, circa 2010, the itch is still there. From a personal perspective, Nyad (as she self-identifies, with a last name that’s Greek for “water nymph”) bristles at the notion that 60 equals sunset. Plus, she sees in society a distinct lack of oomph and believes resurrecting her Cuba-to-Key-West quest can serve as some sort of important inspiration.

Bonnie, whom Nyad once dated “for a second 200 years ago” and is now her best pal, thinks this plan is nuts but agrees to coach Nyad anyway. (Among few unforced attempts at engaging comedy: Bonnie’s realization of just how little there is to do in coaching a swimmer who is a headstrong current unto herself.) Beset by vivid hallucinations, the apathy of potential sponsors, biological limitations, persnickety weather, hungry sharks and pesky box jellyfish, Nyad persists through multiple attempts to complete her journey … and not drive away those who care for her.

Screenwriter Julia Cox punctuates the present day with painfully painted flashbacks to Nyad’s upbringing under a tyrannical father and teen trauma of sexual abuse by a swim coach. It’s precisely the sort of armchair psychology Chin and Chai Vasarhelyi have avoided in their documentary storytelling so far, and Cox also peppers the script with lines like “I signed a contract with my soul to never, ever give up!” or “Your superiority complex is really screwed up, you know that?” It’s also amateurishly time-compressed, showing a newscaster wondering whether Nyad will try a third time and immediately cutting to her jumping in the ocean again.

Depressingly, Chin and Chai Vasarhelyi fare little better with their own attempts at adding flair — from visual effects-assisted shark sequences that feel like previsualization for Meg 2: The Trench and depictions of inbound wind that unintentionally resemble Sam Raimi’s The Evil Dead to full-bloom swimming hallucinations with a Pixar color palette and, worst of all, embarrassingly reductive Indian-tinged music to accompany Nyad’s vision of the Taj Mahal.

It’s indicative of an inability to interest viewers with the innermost thoughts of Nyad while she’s swimming and invest in her identity. The oldies she uses to mentally mark time are first presented with intrigue, Bening’s unaccompanied voice singing “The Sound of Silence.” But then the soundtrack licensing budget kicks in, and eventually, Janis Joplin is blaring from an accompanying boat’s loudspeakers during a raging storm. (As the skipper, Rhys Ifans delivers a few amusingly gruff grace notes.)

If Nyad is never persuasive about the effects of necessarily repetitive motion on its subject’s mind, it’s at least effective in depicting the open ocean’s ravaging effects on the human body. Sunburn, swelling skin, salt stains and the stings of sea creatures are all expertly depicted by makeup department head Felicity Bowring and her team. It also accurately captures the aesthetic absurdity of accouterments and adaptations required to defend Nyad’s body against jellyfish attacks — like a makeshift Pussy Riot-ish face covering or a bodysuit that makes her look like Édith Scob in Eyes WIthout a Face. (You won’t learn this from the film, but such decisions caused controversy in the distance-swimming community on what constitutes “aid”; perhaps it explains occasional, out-of-nowhere persecution complaints Nyad lobs in frustration.)

Meanwhile, Bening and Foster’s instinctive strengths to capture the nuances and shorthand of lifelong friends also propel Nyad and Bonnie’s bond beyond pro forma homily and sitcom quips. But not even these professionals can overcome a despicable scene in which they literally cheer the failure of a younger distance swimmer who also dares to defy the odds. Does Nyad want to inspire others to pursue the wild adventure in the one life they get or is she simply a vainglorious menace? How does Nyad feel about the disspiriting decisions required to fund her efforts, like speaking to a half-full room of dentists at a conference? 

If Nyad isn’t a saint in real life, there’s no need to make her one for the movie; it’s just that Cox, Chin and Chai Vasarhelyi aren’t able to settle on any consistent tone here other than a feeling of tremendous disappointment.