Mysterious and bizarre alien sharks lurk far beneath the waves in remarkably deep waters where researchers are on a quest to make first contact. Pursuing the elusive frilled shark, sleeper shark and cookie-cutter shark bring even more unexpected encounters.

In the Caribbean, a deepsea camera captured footage of a 14-foot tiger shark suffering an assault by a large, unseen beast. It could be an unknown species of mega-shark or even a cannibalistic tiger shark. Dr. Austin Gallagher wants to find out.