For centuries, stories had circulated of an Aztec city so rich that precious gems adorned the buildings and the streets were paved with gold. But like so many Aztec locations, this one had been abandoned and swallowed by the jungle. Since the time of the conquistadors, expeditions have set out to find it. None have ever returned. At their antique shop in 1938, Rick and Rose Sinclair come across what may be a map to the lost City of Gold in an Aztec artifact. The adventurous husband implores his more level-headed wife that this is their opportunity to become rich. She sees it as a chance for a great historical discovery, and agrees. They and pilot pal Humphrey Custis set out for unexplored Mexico.

The three arrive in a jungle filled with perils. Deadly jaguars, killer spiders, and hostile locals all attack at every turn. Rick and Rose soon discover terrifying details about the lost city, including inhabitants that only walked the night and feasted on sacrifices of human blood. The dangers keep multiplying and the Sinclairs are in over their heads. Will they join the list of explorers who died in a search for the City of Gold?