mike ruddson knows that better than anyone.dived with great whites without a cage hundreds of times. he once even caught a ride on a great white's dorsal fin. he insists these animals might be top predators but they're not the man-eating machines so often portrayed in movies. we decided to take him up on his offer to dive with sharks without a cage to see the great whites in their natural state. what do i need to know before going down? >> whatever you do, don't make fast movements. what we are is the same as a jackal at a lion feed. as long as the jackal behaves it doesn't get killed. >> we're like a jackal in a lion feed. the great whites are the lions, we're the jackals. >> exactly. >> they'll let us be there as long as we don't interfere with them. >> don't try to grab a bite and run away. >> the water is filled with chum, fish parts and blood. a number of sharks are already circling the boat. so it's time to go. to get to the bottom, i climb into a cage which is lowered about 20 feet to the ocean floor. mike's already ther