Professor Alice Roberts journeys 40,000 years back in time on the trail of the great beasts of the Ice Age in this BBC documentary miniseries. It begins in the land of the sabre-tooth; North America, a continent that was half covered by ice. Alice traces the movements of Ice Age beasts like bear-sized sloths, vast mammoths and the strange beast known as the glyptodon. These leviathans were stalked by the meanest big cat that ever: Smilodon fatalis. In the Land of the Cave Bear, Alice ventures to the parts of the northern hemisphere, hit hardest by the cold. High in the mountains of Transylvania, a cave sealed for thousands of years reveals grisly evidence for a fight to the death between two staving giants, a cave bear and a cave lion. Yet Alice discovers that for woolly rhinos and woolly mammoths, the Ice Age created a bounty. In the final installment, Alice sets off on her last voyage back to the Ice Age to discover why the giants of the age went extinct.