The novel is set in Rio de Janeiro in the 19th century. Doctor Félix changes lovers every six months —"my loves are every six months; they last longer than roses, they last two seasons"— and he has just broken up with the last one, Cecilia. Viana, his friend, introduces him to his sister Livia, a beautiful woman, widowed for two years and mother of a four-year-old boy. They begin a friendly relationship but, between social gatherings and dances, end up falling in love with each other. At first they live a discreet affair, hidden from society. However, conflicts between them start arising due to his jealousy and mistrust. After many comings and goings, Felix ends up asking the widow to marry him, but he escapes on the eve of the marriage due to an anonymous letter with false accusations against Livia. Thanks to the intervention of his friend Meneses, Félix regrets his thoughtless actions and tries to reconcile with her, but now it is Livia whom no longer wants to marry the immature and unstable doctor. "Doubts will accompany you wherever we are, because doubts live eternally in your heart."—this is how Livia says goodbye to him, diagnosing the reason for her failed relationship.
