In 1912, the RMS Titanic sunk to the bottom of the North Atlantic in one of history's most infamous maritime disasters. After 75 years, it is discovered that Titanic's hold contains a shipment of a rare mineral, the only available supply in the world large enough to power a top-secret and vital United States defense program. When no method can be found of extracting the mineral under more than 12,000 feet (3,700 m) of water, Pitt and his crew set out to do the impossible: raise the Titanic.
Dr. Gene Seagram leads the top-secret Pentagon program Meta Section, which secretly attempts to leapfrog current technology by 20 to 30 years. One result: the Sicilian Project, which uses sound waves to stop incoming ballistic missiles.
The immense power needs of the Sicilian Project can be met only by an extremely rare mineral called byzanium. After satellite data pinpoints the most likely source of byzanium, Meta Section sends Sid Koplin to a small island off the northern coast of the USSR. There he discovers that the byzanium ore has already been mined. While making his way back to his hidden boat, Koplin is shot and captured by a Russian guard but is rescued by the story's protagonist, Dirk Pitt.
Using clues found by Koplin, Seagram determines that the byzanium — a chunk worth more than a quarter of a billion dollars in 1912 figures — was mined in the early part of the 20th century by a group called The Coloradans. The group was hired by the French, but persuaded by the US government to steal the mineral for the United States. Joshua Hayes Brewster and his men engage in a running battle with French assassins as they crisscross Europe trying to get their stolen goods home. Only Brewster reaches England alive, and he books passage on the maiden voyage of the great White Star Line ship Titanic.
Realizing that the only supply of byzanium sufficient to power the Sicilian Project now lies at the bottom of the North Atlantic, Dr. Seagram approaches Dirk Pitt and the National Underwater and Marine Agency and gives them the near impossible task of raising the Titanic. Using data from drop tank experiments Pitt is able to narrow down the search area and began searching with deep sea submersibles. When they find a presentation model cornet that they can link positively to a member of the Titanic's band, they know they are searching in the right place. After discovering that the Titanic is intact, they set out on audacious plan to patch all of the holes and then raise the wreck using compressed air.
While this is happening the Central Intelligence Agency (CIA) convinces the US President to leak information on both the Sicilian Project and the Titanic mission to the USSR in the hopes of setting a trap to capture one of the Soviet's best intelligence men. When the leaders of the USSR realize that the development of the Sicilian Project would throw off the balance of power in the world and leave their nuclear arsenal impotent they do just as the CIA hopes and launch an operation to sabotage the mission or if possible steal the byzanium for themselves.
After Pitt is successful in raising the Titanic and exposing the Soviet spies, all are shocked when it becomes apparent that the byzanium was never actually aboard the ship. This revelation, along with deep troubles with his marriage and the President's agreement to leaking word of the Sicilian Project to the Soviets eventually cause Dr. Seagram to have a nervous breakdown from which he never recovers. It is eventually revealed that Joshua Hayes Brewster, fearful that he would never make it to the United States with the mineral alive, buried the byzanium in the grave of the last of the group to fall to the French assassins in the tiny English village of Southby.