S1, E102: The second episode of the series focuses on the killer dinosaurs. We begin by journeying back 150 million years to the Jurassic period, a time when the first giant killers stalked the earth like the fabled Allosaurus. But killers weren't confined to the land, recent discoveries have revealed an astonishing new hunter in the oceans, a predator that dwarfs almost all others: Predator X