The secrets behind animals' group games, from dolphins that play catch to a hyena tug of war, revealing the benefits they gain from their playful behaviour. The programme examines how breaching the rules of a game can have fatal consequences - but how it also presents an opportunity for animals with a rigid hierarchy to break down social barriers.

The reasons why young animals enjoy playing, and how it can teach them to survive in the wild. The programme explores how young elephants, which rarely leave their mothers' side for the first eight years of life, play to develop social skills, while macaques hone their mental agility by playing games with stones. Plus, a zoologist who looks after orphaned cheetahs reveals how play can help cubs learn to hunt.