In the heart of the largely unexplored Congo Basin forest hides the Mokele-mbembe, a semi-aquatic animal whose shape and dimensions resemble those of a sauropod dinosaur. Do you disbelieve? ‘You are wrong,’ would say Michel, a former lawyer who left everything 15 years ago to try to find the animal. Put on the animal’s trail by one of his trackers, Michel decides to set up his most ambitious expedition yet to finally bring tangible proof of the creature’s existence.