The Paiva family's dog is run over by the dictatorship's goons who are stalking their house. You hear the tire screech and the dog's yelp, and see its lifeless body. (No gore at all.)
One of the Paiva kids, a teenage girl, is brought to an army base where they torture people, and is retained there to intimidate her mom. No physical harm, though.
Flickering camera footage seen at several points, with image distortion including flashes, along with projection light having a mild strobing effect. Some other brief flashing, including when a character wakes up from a nightmare, and reporters using flash photography near the end.
It's about the Brazilian dictatorship in the early 1970, so... of course. You hear the screams of tortured political prisoners when the protagonist is brought to an Army base to be interrogated. No visuals.