produces two reactions. the first is, well, fear. it's hard to believe you're about to actually do this. the second reaction is a surge of adrenaline. it definitely gets your heart beating. mike rutzen knows that better than anyone. he's 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 may be top predators, but they're not the man-eating machines so often portrayed in movies. we've decided to take him up on his offer to dive with the 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 jekyll at a lion feed. as long as the jekyll behaves, he doesn't get killed. >> so we're like the jackal at a lion feed. they'll let us be there, as long