Diver Valerie Taylor, 85, Reflects on Her Amazing Life Undersea in New Doc Playing with Sharks

Ron & Valerie Taylor

"Every dive has the potential to be a great adventure."

So begins the thrilling trailer for the new National Geographic documentary Playing with Sharks, which highlights the life and career of 85-year-old conservationist and photographer Valerie Taylor. The 90-minute film — debuting Friday, July 23, on Disney+ — looks at Australia native Taylor's unique relationships with the animals, whom she's studied and photographed for decades with her late husband, Ron.

Taylor, who still dives, says she "decided to prove that sharks are not out to get us."

"I think sharks know when you're behaving like prey and when you're behaving like an equal," she tells PEOPLE. "Prey pulls away, thrashes around, swims like mad. But an equal looks [a shark] in the eye and swims toward them, acting in a threatening way. And in my personal experience, the shark will either go away or accept you."

Taylor started diving at just 21, learning to spearfish before turning her focus toward the mysteries of sharks and marine conservation. She and Ron filmed scenes for Jaws, were some of the first to dive cageless with sharks and have appeared in National Geographic alongside their breathtaking images.

"It brought back memories," she tells PEOPLE of watching a preview of the documentary. "I was pleased to see Ron's footage being used as it should be used. A lot of it is history — it can never be done again or filmed again, because that life and that ocean doesn't exist anymore."

Indeed, Taylor believes humans are "going backwards" at conservation. "It's obvious, we all know it. We just choose to ignore it," she says. "The only thing that can save all this marine life is nature."

Ron & Valerie Taylor

Recalling her early diving days when the coasts of Australia were "pristine" and the waters full of marine life, Taylor also notes she was one of the few women in the field.

"I never thought about that," she admits. "But I was as good as they were at what they did — I made a point of it. We're going to jump into the water and there were sharks around? I made sure I jumped first."

Now, she's one of the few octogenarians in the field — and isn't slowing down. As she says in the film, "I will probably be diving when I'm in a wheelchair."

Catch Playing with Sharks this Friday, July 23, on Disney+.