In 2016, Beth French attempted to cross seven treacherous channels around the world. Photo courtesy “Against the Tides”

Imagine wading into an ocean in the thick of night, feeling cold swirls of water against your body, looking into the black murk and not knowing what awaits.

In 2016, British marathon swimmer Beth French did just that, as she slipped into the Pacific Ocean off of Catalina Island on her quest to swim seven of the world’s most dangerous ocean channels.

At the time, just six other people had completed what in the swimming world is called the Oceans Seven. French planned to do it in a single year.

“Against the Tides,” a feature-length documentary film by director Stefan Stuckert, recounts the adventure, which begins as the story of an athlete who faced bouts of chronic fatigue syndrome so severe she used a wheelchair as a teen-ager, but flows into a story about a single mom trying to raise her autistic son the best way she can.

The film’s lush cinematography puts the viewer right in the water next to French. Photo courtesy “Against the Tides”

The film made its North American premiere Friday in Austin as part of the Austin Film Festival. A second screening is set for 1 p.m. Monday at the Alamo Drafthouse Village on Anderson Lane.

French, who comes across as a driven athlete who won’t let anything stand in the way of her quest, took five years to prepare for her attempt. She and her team scheduled swims across the North Channel from Ireland to Scotland, the Catalina Channel to the coast of California, the Molokai Channel in Hawaii, Cook Strait between the North and South islands of New Zealand, the Strait of Gibralter, Tsugaru Strait in Japan, and the English Channel.

Along the way, she knew she’d face threats from water cold enough to knock a swimmer unconscious, unrelenting currents, sharks, stinging jellyfish and fatigue. She invested tens of thousands of dollars in the effort, and enlisted the support of hundreds of supporters. She explains, on camera, that she’s taking on the challenge to set an example for her autistic son. The swims vary in length and duration, but the Catalina crossing took more than 19 hours, and pushed French to the brink of exhaustion. The relatively warm, clear waters of Hawaii might seem like a relief after that, but a tiger shark swirled directly underneath her at one point during that crossing. In New Zealand French had to dodge huge, high-speed ferry boats, and during the entire project she faced conflict with her support team and a constant mental battle over whether her swim challenge was negatively affecting her relationship with her son, who has autism.

“It’s been my dream year and my hell year,” French says at one point during the film. “Swimming’s always been the easy part.”

The film made its North American premiere at the Austin Film Festival. Photo courtesy “Against the Tides”

Stuckert, the director, and cinematographer Damian Paul Daniel answered a few questions after the screening. (Stucker will also participate in the Indie Film Track Panel on Documentary Storytelling at 11:30 a.m. Sunday in the assembly room at the Intercontinental Stephen F. Austin, 701 Congress Avenue.)

Stuckert says he knew immediately when he met French that he had a feature-length film on his hands. A mutual friend introduced the two.

“I remember the door opening and a pillow coming straight at my face,” Stuckert says. Beth and her son were in the midst of a pillow fight.

French never regretted what she did, Stuckert told the audience, and is now focusing her time and energy on making sure her son gets a good education.

Stukert spent four years making the film, which premiered in the UK last year. He and Daniel, the cinematographer, captured more than 800 hours of footage, much of it of French swimming, taken from vantage points high overhead, far below and right next to her as she chugged through the water. It’s visually beautiful, and puts the film viewer right in the water next to French and her bright yellow swim cap.

But if you think you know how “Against the Tides” ends, you might be surprised. A ripple went through our audience as the plot shifted, swept away on a new current.

That change reflects the real plot of the film, which isn’t so much about swimming as it is about life, motherhood and relationships.

The plot twist also caused some sponsors to cancel their financial support, and – at the time – made Stuckert think he had a weaker film.

He was wrong.

In the film, swimmer Beth French says she’s completely in her element when she’s in the water. Photo courtesy “Against the Tides”

For more information about the Austin Film Festival, which continues through Oct. 31, go to https://austinfilmfestival.com. For more information about the film, go to www.againstthetidesfilm.com.