S1, E1: In Senegal, West Africa, live a group of chimpanzees, led by an alpha male named David. He has already been alpha for 3 years - a time when leaders here are usually overthrown. To make matters worse, David has no allies - no-one to help him defend his leadership. As the dry season sets in, the group are forced closer together to survive. But for David, he is now surrounded by rivals who all want his crown, and are prepared to kill him for it.