Os Maias is Queirós' criticism of Portugal's decline in the later 1800s. Carlos de Maia returns from medical school to Lisbon to live with his grandfather in the restored mansion, o Ramalhete. In developing his medical practice, Carlos meets and begins an affair with Maria Eduarda, a beautiful young lady he initially believes to be Brazilian. Around the lovers, the city, the Monarchy and many of those they know are in decay. Then Carlos' friend Ega, a writer, discovers that Maria Eduarda is, in fact, Carlos' sister. But despite the revelation, Carlos continues the affair, until his grandfather discovers it and dies.