The film footage would become woven into an iconic scene in the Hollywood blockbuster Jaws, but as the pictures were being filmed events were veering wildly off the script.
As the great white shark drew alongside a small boat, it began thrashing violently, thumping its enormous tail against the vessel.
Lured by the buckets of blood and meat hanging off the side, it had become tangled in the stuntman's cage.
"[The shark] just went berserk," recalls Valerie Taylor, who was watching from a nearby boat as her husband Ron filmed the chaos from underwater.
"The winch started to break off the side of the boat with a terrible cracking sound and suddenly [the cage] broke off and went whirling down."
The cage plunged into the deep. It would almost certainly have taken the stuntman with it had he not hesitated to get inside.
"They found him 20 minutes later and he was curled up with a bottle of gin in his hands," says Wendy Benchley, wife of Jaws author, the late Peter Benchley.
"And he never went back in the water again."
Already a renowned underwater filmmaking pair, Valerie and Ron Taylor had been hired by a then-little-known director named Steven Spielberg to capture live footage of great whites in the wild.
What they delivered helped turn the 1975 film into a surprise hit that terrified audiences around the world, stoking a primal human fear of being eaten alive.
The script was rewritten to incorporate their footage into the climactic action scene in the film.
But for Valerie, it was both a career triumph and a setback.
After years of diving with sharks, she had come to view them not as man-eaters but as magnificent, if misunderstood, creatures in need of protection.
"People became terrified to go to the beach," Valerie, now 87, says of the film.
"Gung-ho men took it upon themselves to kill sharks."
It risked undoing years of advocacy for shark conservation.
Along with her husband, Valerie embarked on a tour of the US talk show circuit, "to tell people that this was a fictitious story about a fictitious shark".
The experience galvanised Valerie's commitment to shark conservation, one that continues to this day with her advocacy for the removal of shark nets from New South Wales and Queensland beaches, which is inspiring a new generation of conservationists.
Few people know sharks like Valerie: up close, in deep water, she has been swimming with them for decades.
She can say, with some pride, that she has only been bitten four times in all those years.
"I've only had one bite where I had to have plastic surgery. I've had three other bites which weren't very pleasant."
And after every incident, she returned to the water. The ocean is her natural habitat, she says. When she is underwater, she is flying.
"I fly anywhere I want. I can see something and fly across to it. It's wonderful, especially when the water is clear."
Underwater film pioneers
Many who grew up in the 60s and 70s would remember the pioneering films that Valerie made with her husband Ron, in which the wonders of the underwater world were beamed into Australian loungerooms.
Together they were a formidable double act: Ron the pioneering cameraman who made his own underwater camera housings to film alien worlds, and Valerie, the intrepid on-screen explorer in her trademark pink wetsuit.
"We would go out there and see things that no-one had ever seen before," she remembers.
"I was long and slender [then]. I'd scare everybody now," she jokes.
Now in her 80s, she has never lost her love of the underwater world.
"In the water I'm young. Out of the water I'm just a stumbling old lady."
She likens those early films to science fiction, "because we were doing things no-one else had ever done before."
She had a knack for interacting with sea creatures, "picking up dangerous sea urchins and octopus", says her nephew and underwater cameraman Jono Heighes.
"Today they pretty much train you not to touch anything because you might disturb it. Valerie and Ron never operated like that."
Valerie's fearlessness, her adventurousness, her sheer guts, can be traced to her childhood in New Zealand.
Her family never had much money, but her mother instilled confidence, bringing up her children to believe they were "beautiful, intelligent, admiring everything we did".
"I thought I could do anything I wanted," Valerie says.
"The world is mine."
At 12, she was hospitalised with polio. But even sitting in bed immobilised, she dreamt of future adventures.
She read Huckleberry Finn and Tom Sawyer, a nurse turning the pages for her.
At 15 she left school and soon moved to Australia, where that self-belief propelled her into an array of different careers: artist, model, go-go dancer, stunt woman, writer and photographer.
By the early 60s, Valerie was doing body double work for television when she heard about a casting call for the play The Seven Year Itch, to be staged at Sydney's prestigious Ensemble Theatre.
"I'd never seen a play, I'd never been to a play," she says.
She "laughed and flirted" with the male lead and got the lead role, played by Marilyn Monroe in the film version.
The play was a success but after nine months, "I was bored. I am definitely not an actress, I'm me. That is what you get on the stage."
Besides, Valerie was in a hurry to have those adventures.
By now her family lived on the waterfront at Burraneer Bay, in Sydney's south, where she spearfished with her father for fish to eat, and she and her brother taught themselves to dive.
She did not go unnoticed in the water and was invited to join the St George Spearfishing club.
"And that's where I met my husband Ron," she says.
"He was the best spear fisherman in the world. And he was beautiful. And he was gentle."
He invited her to swim in front of his camera.
"And she did, and I thought, wow," Ron would say.
But still, Valerie says she would not have made such an impact if not for her ability underwater.
An epiphany
Ron had made a Perspex box for his camera so he could film underwater and soon found a market for the 16mm black-and-white films he was producing, so every weekend they would go out "looking for action".
"It had to be something big, something dangerous, sharks," Valerie says.
When she first met Ron, Valerie had a boyfriend called Gary Shearston, a guitarist and singer who had his own television show Just Folk.
He was "a lovely, beautiful, kind, generous man and very talented", Valerie says.
With Ron on the other hand, it was all spearfishing and filming. There were no dates at the movies. So she gave him an ultimatum — ask her to marry him, or she would marry Gary.
"Ron said, 'Let's get married now'. He could see his on-camera actress vanishing with a singer. That sort of scared him a little."
They started with hardly any money, spending everything Ron earned on camera equipment. But in those early days, "the abundance of life on the Great Barrier Reef was extraordinary".
They would work on their own projects and film underwater sequences for television and major motion pictures, their reputation growing.
It was while they were working on an episode of the iconic Australian TV show Skippy that Valerie had the confronting awakening that set her on a path to shark conservation.
They needed to film grey nurse sharks for the episode and Valerie knew of a place at Seal Rocks, on the NSW mid-north coast.
Even though it looks ferocious, after many dives Valerie came to understand that the much-maligned grey nurse was a docile shark that sleeps during the day and hunts at night.
"We went up there and to our horror, when we went out to the shark gutter, there were all these dead sharks," she recalls.
"Someone, I won't say who, had gone down there and … killed every one."
It was an epiphany.
They vowed never to kill another shark, and gave up spearfishing, deciding just to film sea life instead.
It was also the beginning of a deeper understanding Valerie reached with sharks, which would be captured on film in the 1969 American documentary Blue Water, White Death.
"That was the greatest adventure of our lives," says Valerie of the film, a ground-breaking documentation of shark behaviour made by a team of the world's leading underwater filmmakers and divers.
A woman in a man's world, Valerie insisted on venturing forth from her cage even when discouraged from doing so.
"The director turned to me and said, 'There's no shame in not coming'. I said, 'Oh, I'm coming'."
Armed with only a short pole, Valerie ventured into a school of circling oceanic white tip sharks, one of the ocean's most deadly predators.
The sharks had a reputation for bumping prey before attacking them. So when the sharks bumped Valerie, she bumped them back.
"We had made for ourselves a place in the pack," she said. "And they didn't bother us anymore."
In the early 70s, Valerie and Ron embarked on another film project to show that grey nurse sharks were harmless, but they couldn't find any to film. They were being hunted to near extinction.
"And that is when I went to work to have the grey nurse made a protected shark," says Valerie.
"It took years of letter writing and campaigning."
Later, Valerie contributed to the grey nurse becoming the first shark to be protected by law in the world.
A tireless conservationist
After Jaws came out in 1975, she ramped up her efforts to change how people thought about sharks.
"I realised if they weren't protected they would disappear," she says, "and they were very important to the web of life in the ocean.
"I'd say of over 200 species of shark in the world, maybe four species are really, really dangerous, another four or five are potentially dangerous, and after that they are just pussycats."
She and Ron were tireless advocates for a range of marine animals and gained protections for the gargantuan but friendly potato cod in the Great Barrier Reef.
They never slowed down until illness dictated otherwise.
Ron was diagnosed with acute myeloid leukaemia and after a two-year illness, died in 2012 at the age of 78.
"Valerie didn't want to believe that Ron was sick," says friend and underwater photographer Jayne Jenkins.
"He was always going to get better. He would just say 'I want to live a bit longer.'"
Valerie says she misses Ron "terribly".
"I'd like him back for just a couple of days," she says.
Her salvation was her conservation work, says her friend Kim McKay, the director of the Australian Museum, which is currently staging an exhibition on sharks.
"She could continue with her purpose, which was to tell all of us about the ocean and about the importance of sharks and particularly the grey nurse shark," Kim says.
"That's what's kept her going."
Valerie has remained an indefatigable letter writer, giving lectures, talking to the media about conservation and attracting admiring new generations.
On a recent Saturday on Sydney's Manly Beach, Valerie stood before a crowd of conservationists, young and old, to rally them behind the cause of removing mesh nets from beaches.
"They catch and kill far more protected fish than dangerous animals," she says.
"I don't have much life left I don't think. But I just know what it is like to see beautiful animals struggling in them."
Shark scientist Leo Guida, who has been working with Valerie for the past year to raise awareness about mesh nets and the threats facing grey nurse sharks, acknowledges that not everybody is in favour of removing the nets.
"Some people argue that prior to shark nets there were a lot more fatalities," he says.
"But we're advocating for modern-day methods, like drones."
Late last year Valerie met with Federal Environment Minister Tanya Plibersek to lobby for greater habitat protections for the grey nurse, which continues to be threatened by calcifying fishhooks.
"We've got a new threatened species action plan towards zero extinctions and the grey nurse shark is one of the priority species," Ms Plibersek said during the meeting.
Cheered by the fact grey nurse sharks are on the environment minister's agenda, Valerie is hopeful that her message is finally being heard.
"I feel that the general public are starting to realise that the ocean is an important part of the wellbeing of the planet. But there's a lot to be done and I'm not going to live long enough to do much more."
That 12-year-old girl immobilised in hospital with polio dreamed of having adventures.
But she could never have imagined the life less ordinary that was to come. Or that she would still be diving at the age of 87.
"I keep telling her, 'We're preparing your 100th birthday celebration Valerie. You're going to be there," says friend Mike McDowell.
"She'll go into the box still saying 'we've got to conserve that'."
"Life is an adventure" Valerie says, "all you have to do is live it. Accept it. Run with it."
Watch the two-part Australian Story 'Diving in Deep' on ABC iview.
