Dan O'Neill is on a mission to find and film the planet's biggest living Anacondas. Dan joins Dr. Juliana Terra, a herpetologist in Southern Brazil, hoping to track down a giant female Green Anaconda during the mating season. But it won't be easy when camouflage is one of their greatest skills.

Dan O'Neill is on a mission to find, film, and measure the biggest living crocodiles. Dan joins Dennis, an indigenous saltwater crocodile guide in Australia's Northern Territory, hoping to track down a legendary giant male lurking somewhere along the Mary River.