 Episode 9 - "Guardians of the Deep" Once a lair for pirates and sailors, the islands of Cocos are a mid-ocean oasis that stand alone in the Eastern Pacific. Luxuriant, interwoven rainforest makes for a breathtaking kaleidoscope of green. Spectacular waterfalls crash and tumble into an aqua ocean - this is the landscape that inspired the film  Jurassic Park . This lonely outpost is the largest uninhabited island on earth and is home to an extraordinary abundance of marine creatures that some say is unrivalled on earth. The Quest was drawn to Cocos not by the rumoured riches of buried treasure, but for the islands natural, aquatic treasures. Massive schools of Hammerhead Sharks are Cocos  formidable guardians and these hammerheads host a bizarre dinner party - and willingly place themselves on the menu. They allow themselves to be  cleaned  or fed upon by smaller feeder fish. This symbiotic relationship helps the hammerheads rid themselves of parasites and provides the smaller fish with a ready meal. Scientists here are studying the island and its sharks to see if the burgeoning tourism industry is having an adverse affect on the schooling behaviour of these guardians of the deep.