David Attenborough reveals the life of the hippopotamus as never seen before. With incredible underwater footage, this film delves into the world of the hippo – an animal that cannot swim yet is utterly dependent on water. In Botswana’s Okavango delta, hippos face an unparalleled challenge – deep floodwaters dry to dust in a matter of months. In one extraordinary season, the team go beneath the surface to see them protect their families and face their enemies as they deal with the drought. Going far beyond their dangerous reputation, the show discovers the true nature of the hippo, an animal that is compassionate, sensitive and highly intelligent.