This is the story of two of the most dangerous creatures in the world, hippos and crocodiles, living uneasily together in an African river. Crocs have a remarkably ancient lineage. And some truly impressive distant cousins: the dinosaurs. It is believed that they have two hundred million years of evolution behind them. In most of that time, they have barely changed. This is the story of two of the Nile crocodiles, the most impressive creatures in the world, living together in an African river.