Francis Alÿs is at the same time a painter, a videographer, an urban interventionist and, in his own way, an alchemist. He also hunts tornadoes. Having left Belgium fifteen years ago to settle in Mexico City, he has made the megalopolis a laboratory commensurate with his tireless quest, and his strange walks an art. To share this approach cinematographically is first of all to try to understand the relationship of man to the city, to understand their games, the rules of these games and to play them yourself with images, sounds and words.