Nurse sharks are friendly and curious creatures, like puppy dogs of the deep. But when they suddenly appear out of the darkness at night, it can be a hair raising experience. In the few seconds it took to recognize that this large beast was not a man eater, this diver had some heart-pounding excitement. The shark was likely just curious about the diver or wanted a free meal. Or maybe this is how sharks with a sense of humor prank people. This shark disappeared as quickly as he appeared, possibly off to prank another diver.