Red Fish tells the story of a young woman traveling with her boyfriend. The couple's relationship seems peaceful and happy, but at times, it feels like she's losing him. When he disappears one night in an empty amusement park, the girlfriend's lucidity begins to be tested. Is she dreaming? Was he kidnapped? Did a mysterious force take him? Did he abandon her? Did he ever exist?

Brazil, 1961. In the underground of the Piratini Palace, the governor of Rio Grande do Sul, Leonel Brizola, awaits a bombing by the Brazilian armed forces. The country is on the verge of a civil war, following the resignation of president Jânio Quadros and the movement to keep vice-president João Goulart from taking office. Using the radio transmitter from his improvised bunker, Brizola sets up the Legality movement, to ensure Goulart's right to the presidential chair. Caught in the crossfire, two brothers who are in love with the same woman unite to fight alongside Brizola.