Andy meets the largest mammal ever to walk the earth when he travels back to Mongolia thirty million years in the distant past. On his travels he has a night-time run-in with some hungry hyaenodons and helps a baby paraceratherium out of a sticky situation.

Andy travels back in time three million years to the Great Rift Valley in Africa to meet one of our very own ancient ancestors, australopithecus. During his adventure he has a narrow escape from an angry relative of the elephant and takes a trip in an inflatable dinghy over a waterfall.