Peixe-de-Espada (literally, sword-fish), a retired Army colonel, his wife and nubile daughter are spending their holidays at the Palace Hotel, in the company of a lady doctor, Doctor Pilulas (literally, pills). He tells tall-tales of his African adventures, and she finds ways to promote the excellency of the pills of her own fabrication. To spend some time with Gabriela, his girlfriend, Rito appears disguised as a woman, pretending to be the new post-office operator. Desguises will come and go, and all ends well after a turmoil of twisted plots.

The story of this film is based on actual facts, the murder of actress Maria Alves, and the investigation that ensued, covered by Reinaldo Ferreira himself. Ferreira also wrote a novel based on the same facts.