In a not so distant future, Brazil is taken by a violent epidemic transmitted by a very common brand of mosquito. The lack of alternatives drive the Brazilian government to accept a controversial proposal from North American scientists: to be guinea pig in a nuclear experimen which aims to exterminate the insects. The city of Picuí, Northeast countryside, a place known for its vast uranium reserves, is chosen for the atomic tests. When the American experiment is a failure, Picuí and the region are faced with a much bigger drama: due to the radiation spread in humans throughout the tests, a genetic mutation makes the mosquitos grow in size to proportions never imagined. The population goes wild in panic. The press ask for explanations. Seeing Doctor Harley and his American colleagues flee the country, Pedro Macedo – a brilliant college student in nuclear physics – decides to lead the adventure of freeing Picuí from the threat of the giant mosquitos.
The genre assumed by Yellow Cake is Science Fiction, in its various elements, from the premise of the nuclear tests in the countryside, the disaster generated by the scientists failure, the mutations in the growing mosquitos that take the city. The film has elements of a thriller along with subtle humor, contrasting absurd situations with naturalistic performances. This sense of humor is also employed to satirize the subservience to the richest countries by the peripheral ones.