Warmer waters are now bringing the great hammerhead sharks closer to U.S. coastlines, and shark expert Dr. Neil Hammerschlag is diving in to take advantage of this opportunity to study them. With underwater cinematographer Joe Romeiro by his side, they will put themselves in harm’s way to observe this massive, and increasingly rare predator up close, and attempt to catch and tag one to learn more about its migratory, mating and eating habits.