In 2004, soon after arriving in Australia, I took a boat from Cairns out to the Great Barrier Reef with my then girlfriend.

An hour or so later, seemingly in the middle of the ocean, the boat stopped and dropped anchor next to a floating platform.

We donned our wetsuits, flippers and goggles and plunged into the vast, bobbing ocean. In the back of my mind and I am certain in the back of the minds of everyone in the water that day was: Is there a shark out here?

For the next hour or so we snorkled among the reef, enjoying the colourful fish that swam past and the corals waving in the currents. But try as I might,  I could not get the idea out of my head, that somewhere in that enormous expanse of blue water lurked a perfectly designed grey and white torpedo shaped creature with lots of teeth, who might find a recently arrived pasty South African a tasty entree.

Assurances by the tour operator that large sharks stuck to the deeper channels of water did not re-assure me. After all, what was stopping them from doing a bit of exploring out of their comfort zone on this very day? And what if someone in the water was bleeding? Or splashing about madly?

In the end I was relieved when we hauled ourselves back on the boat, removed our wetsuits and tucked into the buffet spread before the engines were revved up and we headed back to Cairns harbour.

Almost 10 years have passed, but I still remember the feeling of complete helplessness, floating about with nightmarish thoughts circling in my head and the constant need to come to the surface to scour the waves for the familiar dorsal fin.

This week, while hunting for something to watch, I came across the movie “The Reef” on the ABC’s iview.

Made in 2010, it’s about five friends who get stranded in the ocean when their boat hits the reef and capsizes. Four of the friends attempt to swim to an island in the hope of being rescued only to be stalked – and for three of them to  be eaten – by an enormous great white shark.

It is, in my opinion, one just three classic movies made about sharks (excluding those amazing documentaries on National Geographic and the Discovery Channel).

The other two are of course  Steven Spielberg’s Jaws, made in 1975 about a rogue great white shark killing swimmers in the beach side town of Amity Island and the three men (brilliantly played by Roy Scheider, Richard Dreyfuss and Richard Shaw) who set off to kill it and Open Water made in 2003  about an American couple abandoned in the middle of the ocean after a diving expedition and who become the prey for hungry sharks.

Alongside them are litany of terrible, stupid and silly shark movies usually incorporating D grade special effects (the cult film “Sharknado” the pinnacle of silliness), unfathomable plotlines and wooden acting performances that provide stiff competition for the computer-generated sharks.

The Reef  though is one of the scariest and most suspenseful movies I have yet seen, placing the camera in the water as the four suntanned helpless heroes bob about while a huge great white shark circles silently and menacingly, waiting for its moment.

This “in the water” film-making is also employed in Open Water, leaving viewers gasping and shuddering when a fin cuts across the screen.

In both these films, the sharks are all very real compared with “Bruce” the mechanical shark used in Jaws, which famously broke down continuously, forcing Spielberg to use it sparingly, which in the end cleverly added to the suspense.

Jaws is also  pure fiction – based on a best-selling novel by Peter Benchley (he is said to have got the idea from a series of famous shark attacks on the Jersey Shore in 1916) while Open Waters and The Reef purport to be based on or inspired by real events.

Open Waters is based on the true story of Louisiana couple Tom and Eileen Lonergan, who disappeared off the Great Barrier Reef in 1998, after a diving company accidentally left them behind.

However, that is where “true” part of the story begins and ends.

Investigations of their disappearance found no evidence they were taken by sharks. There were wild, unsubstantiated theories they either committed suicide or had hashed some kind of insurance scam, but the official Queensland police was they perished at sea. Dive equipment believed to have been worn by the couple washed up later, but without any evidence of bite marks.

Grahame Connett, of the Port Douglas Marine Tour Operators Association, who ran the Port Douglas Dive Centre told The Age newspaper in 1998:

“There is no indication at this stage that they have been killed at sea . . . There are no bodies, the equipment found has not been shredded. It is almost impossible for them to be taken by a shark. There are not big sharks in the reef area where they were. There are white tip reef or black tip reef sharks. They are docile two-metre sharks . . .

The Reef stands on more solid ground.

It is based on real shark attacks that occurred off the coast of Townsville in 1983 involving trawlerman and lone survivor Ray Boundy and two others who perished.

Mr Boundy told the Courier Mail in 2010, when the movie The Reef was released, that the prawn trawler he was working on capsized with himself, deckhand Dennis Murphy, 24, and cook Linda Horton, 21 on board. The date was July 25, 1983.

They were left in the ocean a day and a half.

Denis Murphy was the first to go in eerily similar fashion to what happens to the character Matt (played by Gyton Grantley) in the film, who after he is attacked yells out “My leg’s gone.”

Mr Boundy said Denis yelled out: “The bastard has got my leg”

The shark or sharks that killed Denis Murphy returned later and killed Linda Horton and also attacked Ray Boundy, who was later rescued by helicopter after swimming to a nearby reef. He  was treated for his shark bites in the Townsville Hospital.

“I knew it was going to be one of us. And then Ms Horton was gone,” he told the paper.

Of course the film is a highly fictionalised and dramatised account of what happened: Pretty girls in bikinis, a romance sub-plot and the wrong species (great white in the film, tiger shark according to Mr Bound). Te film makers also take liberties when purporting to tell the truth, as in final lines at the end of the film

“Kate was rescued the next day by a fishing boat and rushed to hospital…no remains of Warren or the yacht were ever found”

None of which is true. But then again, it hardly matters.

It’s all about primal fear.

Fear, and of course deep respect – something the Western Australian government could learn a thing or two about.

 Further suggested reading:

ABC’s Fact File: Protecting people from shark attacks.

The Conversation: Western Australia’s shark culls lack bite (and science)

The making of Jaws (Youtube video)