At the end of the nineteenth century, two inexperienced Portuguese colonizers, with a vague intention of civilizing the colonies, disembark in a remote part of the Congo River in order to coordinate a trading post.  As time goes by, they become increasingly demoralized by their inability to profit from the ivory trade. A mutual feeling of distrust and misunderstadings with the locals isolate them at the heart of the tropical jungle. Faced with each other, they begin a journey towards the abyss.