Steve Backshall takes on his most deadly challenge in the swamps of Botswana's Okovango Delta. His aim is to swim with the nile crocodile, a terrifying and effective predator that has outlived the dinosaurs, and is feared today by people and animals alike. As he descends into the dark and eerie water world, he encounters an adult female and a huge male crocodile. Creeping close to get a better look, Steve is chased by the male and has to make a quick escape back to the safety of the boat.