It is best known among cult fans as the film that effectively ended the cannibal genre, which, by then, had virtually fallen extinct.

In 2002, British distributor VIPCO released Natura Contro on VHS and DVD as Cannibal Holocaust II, the film's most well known name.

Friends Jemma Demien, Mark, Fred, and Pete head into the Amazon jungle to find a lost professor.

He agrees with her plan and hires Fred and Mark to successfully steal a seaplane, in which the three men fly down to the River Amazon to meet Jemma.

They find a man named Don Pedro, who runs a business that transports monkeys from the wild to zoological gardens.

The group heads into the jungle by canoe (with guides supplied by Don Pedro), where Pete uses a trumpet to greet strangers on the river.

Before they reach their destination and set camp, a small electric ray swims up a guide's anus.

Jemma is forced to act like a monkey, Mark is covered in and bitten by red ants, and Pete is hung tightly to a tree until he negotiates their release by giving the natives a tape recorder.

A young tribal girl, Kuwala, also knows where to find the Imas and agrees to take them there if they help rescue her sister, who the prospectors kidnapped.

They sneak in and overpower the men in one cabin to rescue Kuwala's sister but are captured shortly afterward.

Garcia threatens to have the men's penises bitten off by a snake if Kuwala doesn't tell him where the Imas are located.

They betray Pete, Mark, and Fred by stealing the aircraft and flying back without them, so there would be no one to refute their "discovery" of the Imas.