The Angel of Death sends an emissary to Earth, Adriano, to fetch young Isabella. But he falls in love with the girl and tries to take her evil sister Ruth instead. Death does not accept the exchange, but agrees to give the young woman another opportunity. She can commit two more sins only; if she commits the third, she will die. Meanwhile, the genius Ruth ill-treats her brother, the deaf-mud Tomás - to whom she attributes the cause of all her problems - and lives fighting with Diogo, friend of the family, until she finds herself in love with him.