After unearthing the first Loculus and defeating the Colossus of Rhodes, Jack and his friends are in worse shape than when they first set out. Marco has disappeared without a trace, along with the first Loculus. With no time to spare and no one else to turn to, Jack and the gang have no choice but to follow the only clues they have and to head off on the next leg of their epic quest--to the Hanging Gardens of Babylon!.