While the earliest works of art of mankind depicted horses, the early history of the two species remains largely unknown. From the last nomadic peoples of the Altai Mountains to the Bedouins of the Arabian Peninsula and the Blackfoot Indians, Canadian anthropologist and filmmaker Niobe Thompson traveled the world for two years. He went to meet these communities who live in osmosis with their horses, and tried to understand the history and the nature of the very special bond between man and animal. At the same time, the work of German evolutionary biologist Martin Fischer allows, thanks to a 3D animation, to bring back to life the ancestor of the horse, whose appearance is surprisingly reminiscent of a small fox.