For nearly two months, the USS Newark, carrying an experimental, top-secret military cargo, has been lost at sea. When the sub is finally discovered sixty miles off the coast of California, the government, eager to regain the lost cargo, assembles a highly-accomplished salvage team, accompanied by Dr. Carly Ryan - head of the original project - and her assistant. Unaware of the danger lurking within the sub, the team is sent in to recover the cargo and determine the cause of the ship's disappearance.