Dave Salmoni understands what makes hippos so deadly, but on Zambia's Zambezi River, he's entering a world of African witchcraft and sorcery that makes him rethink everything he believes about animal attacks. As a zoologist, Dave struggles to explain Zambia's most vicious hippo attacks, until his scientific approach meets local beliefs. He enters a world of witches and witchdoctors, where evil sorcerers possess hippos and make them kill. Dave is skeptical until he witnesses a hippo exorcism ceremony that leaves him amazed and confused. After this journey, he never will look at animal attacks the same way again.