At the end of the 16th century, ships full of gold from the colonies in America dock in Portugal and England every day. The main profiteer is the Fugger family. When a galleon with a secret cargo sinks off Portugal, the Fuggers' business is in danger. They send out their spy Amman Sachs to solve the case. The trail leads him around the globe right into the heart of London, where the fledgling English secret service is spinning a sinister intrigue. Amman Sachs realises that the cargo of the sunken galleon is far more valuable than gold - and a thousand times more dangerous.