Sequeira, a major businessman in the finishes industry, is found dead near the Santo Inácio Zoo, in Avintes. On his body, two clues are discovered: a red fingernail and a photograph of a mysterious woman. Guedes, a private detective, is hired to solve the crime. Who is the mysterious woman? Where is the former Dragão Sandinense, Crespo? And most importantly, where is Sequeira's fortune?