A Spanish historical drama series set in 17th-century Madrid, following a schoolteacher who secretly operates as a skilled vigilante hero known as the Red Eagle, dispensing justice to the oppressed whilst concealing his double life from those around him. He navigates dangerous conspiracies involving the Spanish court and the Inquisition, all whilst raising his young son and contending with a loyal but bumbling servant. The series blends swashbuckling action with serialised mystery plots and achieved considerable popular success in Spain.