Reporter: Scott Pelley, CBS 60 Minutes
Producers: Henry Schuster, Rebecca Peterson
It's one of the most amazing spectacles on earth, millions of wildebeest, travelling hundreds of kilometres across Africa's vast Serengeti Plain.
They go north in search of food and water, flanked by graceful zebra and gazelle. It's a treacherous journey.
Cheetah and hyena shadow their every step, while hungry crocodiles lurk in the rivers they must cross.
Predator and prey, life and death, it's as magnificent as it is horrific.
But, as Scott Pelley of American 60 Minutes discovered, this great migration is under threat and, if we're not careful, could disappear forever.