In Rio de Janeiro, the teenager Silene is approached on the street by the middle-aged Dr. Odorico Quintela that asks information about her mother Engraçadinha. They take a cab to the suburb of Vaz Lobo where Silene lives and the swindler Odorico tells Engraçadinha and her husband Zózimo that he was a friend of Engraçadinha's father in Espírito Santo. However, he gets close to Engraçadinha expecting to seduce her and have sex with her. Meanwhile Silene's boyfriend Leleco invites her to go with him to an apartment to make love. However, Leleco's friends Cadelão, Cabeça de Ovo and Bob plot to break in the apartment and rape Silene. However, Leleco goes to a motel instead and his friends try to rape him later in Cadelão's apartment. Leleco kills Cadelão in self-defense but the police arrest his next door neighbor professor Petresco, who is married to a younger woman. The journalist of O Dia - A Notícia newspaper Sabiá discovers that Leleco is the killer and Dr. Odorico defends the ...