An exploration of a theory of how AIDS was introduced to the human population. Illustrates the thesis presented in Edward Hooper's book The river : journey to the source of HIV and AIDS, and expands on it with new reporting. Many believe the answer lies in the research undertaken by scientist Hilary Koprowski, who between 1957 and 1960, injected his experimental polio vaccine into almost one million people in the former Belgian Congo. The film interviews scientists and journalists, as well as Africans who worked in the labs where the alleged vaccines were made, and also documents the ongoing battle between journalists and scientists in proving the theory's viability.