An oil spill around Isle V is putting marine life in danger. Only the vampire squids can get rid of the oil so that life on the reef can get back to normal. Kevin and the other sea creatures must make the journey to the deeper sea to fetch the squids. But how can they succeed when they must get past the bull sharks who want to eat them? They will also have to swim across the underwater vents which are teeming with giant blood-sucking bacteria. But these are nothing compared to Kevin's fight for his life as he uses up all his air and the others must find oxygen for him. Will the mean old sponge give up its oxygen for free or will this be the end of Kevin's adventure, even before it has begun?