The key to primate success is that, like us, most species live in close-knit family groups. How do you choose your friends, learn from those around you and know who to trust? We explore the complex world of primate social lifestyles.

Our primate cousins are much smarter than you might imagine. Just like us they use tools, solve problems, and even have emotions. George witnesses the largest monkey party in the world, goes to orangutan school in Sumatra and meets a bonobo that can light a fire to toast its own marshmallows. In Thailand long-tailed macaques floss their teeth with human hair. Chimps pass on customs through generations and in India adrenaline fuelled monkeys take extreme sports to a surprisingly human level.

Dr George McGavin gets up close and personal with Siswi, an orangutan who uses soap to improve her personal hygiene. He strips off to experience the mind-numbing cold of the Japanese Alps, and heads 100 metres underground to a secluded monkey dormitory. Then there are baboons with a thirst for flamingo flesh; macaques with criminal minds; fluorescent mandrills who wear war paint to do battle; and Ardry, a real-life gremlin who sees the unseeable with her extraterrestrial fingers.