**From the #1 New York Times bestselling author of Jurassic Park and Timeline comes a gripping thriller about the shocking demise of eight American geologists in the darkest region of the Congo.

“Thrilling.” —The New York Times Book Review**

Deep in the African rainforest, near the ruins of the Lost City of Zinj, a field expedition is brutally killed. At the Houston-based Earth Resources Technology Services, Inc., a horrified supervisor watches a gruesome video transmission of that ill-fated group and sees a haunting, grainy, man-like blur moving amongst the bodies. In San Francisco, an extraordinary gorilla named Amy, who has a 620-sign vocabulary, may hold the secret to that fierce carnage. Immediately, a new expedition is sent to the Congo with Amy in tow, descending into a secret, forbidden world where the only escape may be through the grisliest death.