The venture, an old trident nuclear submarine retrofitted for research has picked up an ancient and powerful artifact off the ocean floor and brought it onboard. Called the Hades Stone, it allows the dead to come back through and join the living. No one has entered the portal, but evil things have come back through into our world - phantoms, demons and an ancient bad-ass known as 'the stone keeper, guardian of the Hades Stone'. (jbhifionline)