Historian Bettany Hughes investigates the ideas of ancient philosophers, starting with the Indian nobleman Siddhartha Gautama, more popularly known as Buddha. Thought to have been lived and tought between the sixth and fourth centuries BC, the sage and holy man inspired a diverse belief system that influences the lives of millions of people to this day. She travels to India, where Buddha experienced the challenging ideas and extreme methods of wandering `truth seekers', after he had abandoned his family and homeland in the Himalayas to embark on his philosophical quest to find a solution to human suffering.