This film does exactly what a documentary should do: Get you close to the subject. In this case, it's the Tropicalia movement of the late 60s in Brazilian music, which is (I think) one of the more important manifestations of popular culture in the world. The film primarily focuses, year by year, on the two main players: Caetano Veloso and Gilberto Gil. It traces the background of the movement and how it rebelled against both leftist political song and mindless pop to create a new Brazilian type of popular music. It moves quickly, with lots of intercutting. You need to read the subtitles carefully if you don't know Portuguese. You also need to something about who the major people are, in advance, because the director seems to expect a certain level of prior knowledge about people such as Tom Ze, Gal Costa, Helio Oiticica, Rogerio Duarte, and a few others. The film sticks pretty closely to chronology, which helps. There is a also great deal of priceless footage of the musical acts and the controversy that they caused. After the two main players a forced into exile, the film slows down a lot, but by then you have already learned a tremendous amount. Overall excellent.