A small oil platform located on a small river in Louisiana hits it big and former oiler John Sanders (who quit when a blowout occurred on a rig he was the boss of and four men died) and his friend Emery are hired to take his ex-wife Kelly and her boss to the location. Nearby, some thugs go diving for stolen goods that have been dumped in the river. Unfortunately, at the same time, a huge bull shark enters the river. Emery's people, a local tribe, believe that the shark is the physical manifestation of a spirit that supposedly protects the area where the well is located, brought forth as a form of vengeance for the driller's activities.