France, May 1940. As the German army blitzes Europe and Parisians flee their city, the chief curator of the Musee de l'Armee is ordered to take a mysterious piece of cargo out of the country. But when he learns his intended ship has been sunk, the fate of his cargo must rest on a decrepit steamer, sailing out under German fire... Decades later, a diving expedition in the English Channel leads Director Dirk Pitt to a cache of uncut diamonds on a shipwreck. No sooner than they are discovered, the diamonds are stolen! Pitt and the NUMA agency now find they must face a murderous cabal with far more destructive plans than mere theft. Vital water treatment facilities around the globe are being targeted - placing the world's population in grave peril. Only Dirk Pitt and his children, Summer and Dirk Jr., can locate the treasure that will save the world from catastrophe.