Annie and her new SWAT boyfriend take a romantic cruise to the Caribbean. The ship is infiltrated by a crazy, bitter, demon, genius who is adept at computer and is intent on blowing up the ship and destroying all on board.
Annie (Sandra Bullock) and her policeman boyfriend Alex (Jason Patric) decide to take a romantic ocean cruise together. Once at sea, however, a disgruntled passenger has other plans. John Geiger (Willem Dafoe), the designer of the ship's computer system was fired and cast aside by the computer company he worked for, and now he wants revenge. He’s set the ship on a collision course with an oil tanker anchored at the island of St. Martin, and now it's up to Alex to stop him. But can he outwit a man who can control the entire ship from his keyboard?