The film deals with oil exploration in the Ecuadorian rain forest and the ecological and social catastrophes it is causing. It begins with the history of the conversion of the Huoaranis, who until a few years ago were regarded as the last Stone Age people, but now are under the control of fundamentalist Christian missionaries and oil companies. We pursue the catastrophic consequences of oil exploration in the rain forest that can be seen in the Cofan tribe, which has been the hardest hit, and talk to its white president, Randy Borman.
The experiences of the Cofan have inspired the resistance movement of the Quichua tribe in the province of Pastaza. The festival of abundance celebrated in Sarayacu (which has never before been filmed) shows the power of this tribe's own culture and its will to defend its own way of life to the end. "The Voice of Heaven" is an expanded and commented segment of the longer film "The Americas".