The cunning Senator Petrônio Paranhos gives an interview to the beautiful journalist Magali Santanna, who is interested only in his affair with Arlete—an ambitious young woman intent on conceiving the older man's child via in vitro fertilization. To land this scoop, Magali agreed to interview the politician in a motel room, a condition he had insisted upon. However, Paranhos suffers a sudden collapse and dies during the interview. Detective Aristênio Catanduva, who had been keeping the senator under surveillance, investigates the case. Known by the codename "Araponga," he is a bumbling figure working for the Federal Police following his long service to the military regime.