A Conversation with Petra Costa the Director of the documentary “The Edge of Democracy.” It is the last film in a trilogy by Brazilian actor and filmmaker Petra Costa. Each film explores the personal and political dimensions of her life, her family, and her country. The Edge of Democracy, however, is by far the most overtly political. With unprecedented access to Brazil’s previous two presidents, Lula da Silva and Dilma Rousseff, Costa document’s the rise and fall of not just two presidents and their party, but the integrity of Brazil’s post-dictatorship democracy and with it the hopes of an entire generation.