I don't think it matters whether it all was real or made up (although I know most of it was horribly real). What matters the most is that it all actually could happen and it doesn't surprise a modern man anymore. This world is wicked, people are wicked and this movie makes us realise that very well. Additional asset is the brilliant and witty narration, full of sarcasm but - what the hell?! - not even a bit racist!!!
The exploitation classic that set the mold for the "mondo" genre and remains one of the best. An exhilarating whirl of lurid sensationalism (though horrifically dated in its cultural attitudes) told with surprisingly inventive and witty editing and camerawork, all set to Riz Ortolani's superb score. Jacopetti and Prosperi would get more ambitious with their later mondo efforts, but this is a classic of its kind.