Plot: The Venture, an old Trident nuclear submarine, has picked up an ancient and powerful artifact called the Hades Stones off the ocean floor and brought it onboard. THE STONEKEEPER, guardian of the Hades Stones who is sinister and powerful, is intent on destroying the sub survivors and taking them back through the portal. The stonekeeper and his stone demons attack, killing the entire Venture crew. The portal inside the Hades Stones fills the sub with the accursed souls of the past. A distress signal goes out from the submarine. Then nothing, no further contact. Jack Bavaro, head of Interceptor Force, realises the Hades Stone and its demons may have taken over the sub and simply destroying the submarine with a torpedo won't work. So now it's a battle at the bottom of the ocean for the Phantom Force to destroy the Hades Stone and save the world from never-ending evil.