Deep in the Congolese jungle is a band of apes that, according to local legend, kill lions, catch fish and even howl at the moon.
Local hunters speak of massive creatures that seem to be some sort of hybrid between a chimp and a gorilla.
Their location at the centre of one of the bloodiest conflicts on the planet, the civil war in the Democratic Republic of Congo, has meant that the mystery apes have been little studied by western scientists.
Reaching the region means negotiating the shifting fortunes of warring rebel factions, and the heart of the animals' range is deep in impenetrable forest.
But despite the difficulties, a handful of scientists have succeeded in studying the animals.
Early speculation that the apes may be some yeti-like new species or a chimp/gorilla hybrid proved unfounded, but the truth has turned out to be in many ways even more fascinating.
They are actually a population of super-sized chimps with a unique culture - and it seems, a taste for big cat flesh.