They are known as one of the most dangerous sharks in the world - as footage of this terrifying bull shark attack seems to prove.
Diver Kerry Daniel, 35, was spearfishing off the coast of north Queensland near the Great Barrier Reef when he recorded the moment the predator charged at him.
Fortunately he was able to jam his spear gun into the shark's mouth, leaving the creature writhing in pain while he escaped uninjured.
But as the video shows, a moment more of hesitation and the roles could have easily been reversed.
Daniel, who runs spearfishing channel Liquid Vision, told Daily Mail Australia that he was on a trip with friends when the attack happened.
He said: 'We've done this trip once a year for the past six years.
"We've had reef sharks come up to us before, they might take a fish off your line after you shoot it, but nothing like this."
He explained that he was fishing in a channel off the northern-most tip of Queensland when he swam away from the main group.
He saw the shark swimming 50m below him, and tried to steer clear of it.
But he said the creature immediately turned to face him and started swimming towards him.
He was expecting the predator to give him a bump, as sharks often do when unsure about prey, so kept the spear gun ready.
It was only in the last 6m, Daniel said, that the shark charged straight at him.
With no time to think, he plunged the spear gun straight into its mouth before leaving the beast writhing underwater.
He added: "He ripped the gun out of my hand, ripped the line off too. I didn't realise the gun was stuck in his mouth so I was waiting for him to spit it out but then thought it wasn't worth it and swum away."
Daniel, who also manages a pesticide business, said he does not know what became of the shark.
But he has spoken to several shark experts and experienced spearfishers who say they have not seen that kind of aggressive behaviour before.