The adventure of Niaux -- The greatest mystery -- The Neanderthal enigma -- The roots of language -- Abbe? Breuil -- Font-de-Gaume and Combarelles -- The tale of a missing dog -- The sign of the bull and the legend of the minotaur -- Rouffignac and Pech Merle -- The discovery of Lascaux -- The enigma of the pit -- The groundbreaking work of Annette Laming-Emperaire -- Prehistoric objets d’art -- The sign of the hand -- The legend of the white lady -- Shamans of the tundra -- Stonehenge and signs in the sky -- The Mediterranean, Australia, and Patagonia -- Leroi-Gourhan’s theory -- The relationship between signs and animals -- The Chauvet cave.