Congo

Congo is a 1980 science fiction novel by Michael Crichton, the fifth book published under his own name and the fifteenth of his career. It is a lost-world story: a party goes into the Congo in search of diamonds and to find out what killed the members of an earlier expedition, and the answer lies in the forest and in a ruined city.

The second expedition includes a primatologist whose gorilla, Amy, has been trained to communicate in sign language, and the technology of the period is part of the plot: the team carries equipment for laser communication and satellite imaging, and the story is told partly through the documents and data they send back. Between them and the site is a country in the middle of a civil war and a range of mountains nobody has crossed.

Crichton wrote the book after a period of interest in primate language research and folds that material into an adventure structure rather than a lecture. It was one of his early bestsellers, and it is the novel in which his habit of building a story out of real technical detail is most visible.