Cheeky, farcical and allegorical "true story" of the dawn of mankind. In the year 196303 BC, after a tribe of cavemen figures out how to have sex, O is born and, being different and more evolved than his xenophobic apeman and neanderthal family, immediately kicked out of their cave at birth. Young abandoned brontosaur Igua befriends him and takes care of him. While growing up, O befriends other dinosaurs as well, but once he realizes that he's not a dinosaur, he decides to find his own path in life and brakes off his friendship with Igua in a fit of anger. Igua wants to mend their friendship and decides to look for O until he finds him again.