After a Nuclear Submarine Mysteriously Sinks In a Remote Part of the Ocean Floor, a Team of Divers On a Prototype Underwater Oil Rig Are Pressed Into Service By the U.S. Navy In a Rescue Attempt. When a Hurricane Cuts Off Contact Between the Surface And the Underwater Depths, the Crew Begin To See Evidence of a Strange, Possibly Alien Intelligence At Work. While Chief Bud Brigman (Ed Harris) Bickers With His Ex-Wife And Boss (Mary Elizabeth Mastrantonio), the Navy Commander Begins To Grow Increasingly Paranoid About the Mysterious Alien Life And Threatens To Use a Recovered Nuclear Weapon To Destroy Everything.