The discovery of blue diamonds in the ancient city of Zith, now lost in a remote African jungle sends scientists from various countries scrambling to gain possession of the treasure, which is an essential component in revolutionary ultra-computer technology. After tracking down the location of the lost city using super computers, a team of American researchers led by a woman is sent along with a sign-speaking gorilla named Amy. They have to contend with cannibals along the way, a hostile government, an erupting volcano, and a mysterious creature that had wiped out a team sent earlier, their brains bashed out with incredible force. It turns out that the creature is a gorilla. There is a whole lot of them: descendants of simians trained by the ancient rulers of Sith to guard the mines from intruders. They were taught to strike their prey using twin clubs in devastating fashion. In time, the gorillas rose against their masters and became rulers of the realm. When the humans disappeared, the gorillas defended the lost city with the same deadly efficiency as their forebears. Running short of ammunition and supplies, besieged by a cunning adversary, the frightened team appears headed for annihilation. Can Amy the gorilla save them? If you are a fan of futuristic fiction, it may be worth your while finding out.