Tom Allen and Peter Gros have traveled to the waters of Dangerous Reef off the southern coast of Australia, to observe the attack behavior of the Great White Shark, with researcher Jeremiah Sullivan, to test a new armored diving suit. Tom and Peter first dive in the shallows and swim free as they watch the prey of the sharks, Australian seals and sea lions. A shark comes toward them, and they take refuge in the shark cage, which is furiously attacked. Later, testing a small mobile shark cage, Tom is attacked by an enormous Great White Shark, who severs his air line, power hose and tether to the mother ship, and Tom barely escapes with his life. Finally, the armored suit, designed by Jeremiah, is tested on a dummy that has been filled with fish bait. A shark comes and attacks the cage savagely, then goes after the dummy. An inspection of the dummy afterwards shows that the armored suit did in fact provide important protection.