This third instalment of Walking with Beasts goes back 25 million years ago to meet the biggest land mammals of all time - the Indricotheres. Up to 7 metres tall and weighing 15 tonnes, adults were too big to be eaten by any predator of the time. In fact it is only in the first few years of life that Indricotheres are vulnerable. This programme follows the fate of a calf from his traumatic birth to see whether he can survive droughts, six foot tall killer hogs and Hyaenodon - a predator the size of a rhino, with jaws that could crush a rock. Show less