Of all the animals in the oceans, the hammerhead shark may be one of the strangest looking. The exact purpose of the wide, flat head is a mystery, but several theories abound. We travel to the shark-infested waters of the Galapagos in Ecuador to learn about the unusual habits of these sinister-looking sharks. Jonathan swims in schools of hundreds of hammerheads, and yet the sharks ignore him. What are the sharks up to?