Philippe Desmond, 65, is found dead at home, victim of an Aztec ritual sacrifice. The heart of this former archaeologist turned treasure hunter was extracted from his rib cage and then placed in a sacred urn. Raphaëlle and Astrid then go in search of the victim's adopted son, Necalli Cantu, a young Mexican living hidden in a forest. Questioned, the latter reveals to Raphaëlle that his father had found the Eldorado, the mythical land of South America supposed to be full of gold. According to him, he was killed because of his discovery ...