reporter: the film jaws has a lot of answer for in whipping up fear and misunderstanding about the great whiteshark...one of the world's greatest apex predators...but that terror has also lead to a tourist boom in south africa. >>scott: gansbaai ...200 kilometers east of cape town and home to the greatest concentration of great white sharks in the world ...and people just love to come and see them. >>shark-cage diving is now thought to be the number one adventure activity in south africa. in gansbaai alone, it brings in around 40 million dollars a year..with hollywood helping all the way: >>doo, duh, doo, duh doo duh..you find its very much just like propaganda, the media portray things in a certain way. >>oh yes, jaws made me quite scared... >>reporter: kim 'the sharklady' maclean pioneered shark-cage diving in 1992. she is one of only a few recognizedoperators in south africa. she's passionate about the animals. >>maclean: i actually started the shark cage diving many years ago and really at the back of my mind was to educate people and to simply to take people out with their fear and bring them