The action begins and takes place in Antarctica.

The famous Dirk Pitt, the hero of so many Clive Cussler novels, focuses on the descendants of a couple who survived a 19th century battle between survivors of a penal colony on a deserted island, and their jailers and is called upon after an unknown cataclysm has killed thousands of marine animals and nearly 200 people aboard a cruise ship.

Many hypotheses are proposed for what is causing these disasters. The most viable one seems to be a tidal undersea wave that combines with others to cause a powerful and devastating wave.

At the beginning of the book Pitt rescues Maeve Fletcher, one of the descendants of the original survivors. 

Later he traces the carnage to the global diamond operations of Maeve's father, Arthur Dorsett, and her two callous sisters who aim to corner the world's diamond market and become super rich.

They have kidnapped her two small children and are keeping them as hostages.

There follow a series of typical Cussler adventures - a chilling escape from a high-security mine in Canada and a harrowing account of surviving on a tiny boat adrift on lonely shark-infested seas, far from the shipping lanes and without navigational aids.

But as always Pitt keeps racing to thwart Dorsett's ruthless plans before an unthinkable disaster claims millions of innocent lives.