Nick Caine and Ishi Cuyamel return to the United States with heavy hearts following a series of unexpected surprises in Scotland... surprises that have left them without Marie Da Vinci while placing the pair in the coerced employment of a secretive United States government agency.

Rather than face the threat of extended jail time, for their role in looting precious artifacts from throughout the world, Nick and Ishi agree to give up their livelihoods as 'creative archaeologists'. If only working for 'Project Golden Eye' was that simple.

Nick and Ishi's first assignment should be one that plays to their strengths and familiarity, since it involves yet another lost 'city of gold'. However, as this particular ancient metropolis lies somewhere deep in the Amazon jungles of Ecuador, it does not carry the renowned status of most other legendary sites in South America. What it does bring, is the very real danger of losing one's head to the ruthlessly brutal Javaro tribe-best known for their fierce independence from modern society and the ancient practice of shrinking their enemies' severed heads.

To avoid their beloved noggins becoming belt ornaments, Nick and Ishi must outsmart a cunningly evil adversary, while also resisting the instinctive urge to collect artifacts from a treasure heretofore believed to be purely mythical.

Can the pair can survive these perils and more lurking in the upper Amazon Basin? The answer lies in the mystery of the River of the Damned...