The Okavango river in south-west Africa is home to a lot of crocodiles. These ferocious predators are known to attack humans, and few sights in nature compare to the savagery of a feeding frenzy. We follow Roger Horrocks as he prepares to dive with crocs. We hear from croc attack victims and locals with knowledge of crocodile behaviour. And finally, we take the plunge as Roger enters the water and comes face to face with a 4-metre giant.