Congo

Set in June 1979, the story follows a high-tech American expedition racing into the remote northeastern Congo rain forest to locate a fabled lost city and its diamond mines before a rival Euro-Japanese consortium can reach them first. The narrative covers 13 days in the jungle, drawing parallels to Henry Morton Stanley's 19th-century explorations while emphasizing that African exploration has become dominated by corporate interests.

The story opens with the violent destruction of an Earth Resources Technology Services (ERTS) geological expedition camped near the Virunga volcanoes in Zaire (now the Democratic Republic of Congo). The expedition's guide, Jan Kruger, discovers that a porter's skull has been crushed by an unknown force. Before the attack, local porters had warned that the area was called kanyamagufa, "the place of bones," where skulls would be crushed by dawa, or magical forces.

In Houston, Karen Ross, the 24-year-old ERTS Congo Project Supervisor and a mathematical prodigy, watches garbled video of the destroyed camp. Using sophisticated image-processing software, she extracts a clear image: the face of a male gorilla. Her boss, R. B. Travis, dismisses it as a computer artifact, but Ross proves the image is real. Travis plans to send a new expedition within 96 hours. The stakes are enormous: ERTS is searching for Type IIb boron-coated blue diamonds, rare semiconducting crystals essential for next-generation computers and military technology. Whoever finds a natural source gains a multi-billion-dollar advantage.

Ross contacts Dr. Peter Elliot, a 29-year-old primatologist at UC Berkeley who runs Project Amy, a research program centered on a mountain gorilla named Amy. Elliot has taught Amy over 620 signs in American Sign Language. Amy has recently begun having disturbing dreams, producing finger paintings of crescent-shaped doorways surrounded by jungle. A research assistant discovers that Amy's drawings closely match a 1642 Portuguese engraving of the legendary Lost City of Zinj, a fabled source of diamonds known to Arab traders since the seventh century. Elliot believes Amy may possess a genetic memory of the city, since she was taken from Africa as an infant. When Ross reveals that ERTS satellite imagery has located the actual ruins, Elliot volunteers to bring Amy along.

The expedition departs San Francisco on a cargo jet. In Tangier, they recruit Captain Charles Munro, a former Congo mercenary and the best bush guide in Africa, after a tense bidding war with the consortium. Machine-gun fire rakes Munro's house as they finalize the deal, underscoring the consortium's willingness to play rough.

In Nairobi, consortium agents kidnap Amy using a tranquilizer dart. Ross tracks Amy through a swallowed transmitter and recovers her from an automobile junkyard. The team also identifies the body of a geologist from the first expedition: his arms show bilateral crushing injuries, and gorilla blood is found under his fingernails. The expedition transfers to a smaller Fokker prop plane with Munro's eight Kikuyu porters and departs for the Congo.

Flying over Zaire, the plane draws surface-to-air missile fire. Ross deploys radar-confusing chaff while Munro reveals a plan concealed from Elliot: They will parachute onto Mount Mukenko's barren southern slopes. The missile attack forces a jump 80 miles south of the intended drop zone, and Munro pushes the terrified Elliot out of the plane. After reassembling on the ground, the group begins a 200-mile trek through the Barawana Forest, passing through Kigani territory where they observe cannibalistic warriors.

The following days bring a grueling descent into the rain forest. A detour to a pygmy village reveals Bob Driscoll, a catatonic survivor of the first ERTS expedition. The team takes to the Ragora River on inflatable rafts, surviving a terrifying whitewater gorge. Munro's plan to pass hippopotamus territory at night fails because they arrive too early, and a bull hippo attacks and destroys one boat.

After climbing Mount Mukenko, the team receives devastating news: Houston confirms the consortium has already reached the Zinj site. No one is willing to quit. They descend through the volcano's smoking crater and push on, passing through kanyamagufa, a field of shattered bones where Elliot secretly identifies fragments of gorilla and human skulls. They come upon the consortium's C-130 transport plane, shot down and wrecked in the jungle, its cargo doors unopened. They find the consortium camp in ruins, every member dead with crushed skulls, identical to the first ERTS team's fate. Guided by crossed laser beams positioned earlier on the volcano, they reach the moss-covered stone blocks of the Lost City of Zinj. Amy has vanished.

The team sets up an electrified perimeter defense and explores the city. Computer-enhanced video reveals painted bas-reliefs depicting a prosperous civilization that traded diamonds. Nighttime attacks begin: eerie wheezing sounds surround the camp, and something contacts the electrified fence. Fresh footprints reveal triangular primate tracks, and gray fur is caught on the wire. A porter is found dead, his skull crushed by stone paddles from the ruins. Amy returns after several days with wild gorillas, explaining through sign language that she left because she felt rejected but came back because she missed Elliot. She insists the attackers are not gorillas, signing "Bad things come."

Deeper in the city, they discover the key to the mystery. Behind a temple containing a massive gorilla statue holding stone paddles, bas-reliefs depict a training sequence: The Zinjian people trained gorillas as guards for the diamond mines. Centuries after the civilization vanished, the gorillas continue teaching each other aggressive behavior. Elliot examines two killed attackers and determines they represent at least a new race, possibly a new species: uniformly gray, smaller than known gorillas, with lighter eyes and cranial features resembling chimpanzees.

A massive solar flare cuts satellite communication, leaving the team without Houston's computers. Elliot realizes Amy can translate the gorillas' vocalizations and records her interpretations. Working with limited equipment, the team constructs a crude loudspeaker and composes three messages in the gorilla language: GO AWAY, NO COME, and BAD HERE. That night, a torrential rainstorm shorts the perimeter fence, and the gorillas launch a devastating assault. Porters are killed and defenders overwhelmed. At the last moment, Elliot activates the broadcast. The rain eases, and the gorillas freeze, listening. Confused by the sounds, they withdraw one by one into the jungle.

The next morning, the team locates the diamond mines, extraordinarily rich with protruding stones. Ross places explosive charges for a seismic survey, but Amy accidentally detonates them, and Mount Mukenko erupts. A catastrophic earthquake collapses the city as lava descends the slopes. The Lost City of Zinj is buried forever. The expedition flees through ash, lightning, and volcanic gas, sheltering inside the consortium's wrecked C-130 transport plane. Kigani warriors besiege the plane until Munro kills their sorcerer. Ross discovers propane cylinders and the consortium's hot-air balloon equipment aboard the transport and inflates the balloon. It lifts off, carrying them over the volcano and across the Rift Valley toward Kenya.

In the aftermath, Travis cancels the Blue Contract, ERTS's initiative to secure a natural source of Type IIb blue diamonds, reporting that no such source can be found. Ross resigns from ERTS and marries. Elliot takes Amy to Zaire to study her interaction with wild gorillas. She disappears in May 1980 but returns months later with an infant who signs to Elliot before Amy retreats into the bush. Munro sells blue diamonds in Amsterdam and continues his adventurous life from Tangier.