This book chronicles a shipwreck of a Spanish treasure galleon that was taking treasure from south America to Spain when it was pursued and sunk by a contingent of British ships. What was different about this ship sinking is that it sunk fairly intact, unlike other ships that sunk at this time was that they other ships were sunk mostly by storms, and their cargo was spread over a large area. The fact that this sunk intact meant that they treasure sure be in one place. This was a well known treasure ship for many years, but the general knowledge was that it was in a location where it was not.
The author also spends a lot of time putting the ship in context by providing a history of Spanish colonialism in central and south America. The ship was found within the legal waters of Colombia, but when it was found Spain tried to assert that it was their ship so their treasure. However, the fact that there is no longer a Spanish empire took precedent over Spain's claim. The author also goes into the history of treasure hunters and the international laws that govern this kind of treasure.