An investigation into a retired WWII sub plunges a research team into a supernatural journey across the dark abyss of time - with history hanging in the balance. An investigation into a retired WWII sub plunges a research team into a supernatural journey across the dark abyss of time - with history hanging in the balance. An investigation into a retired WWII sub plunges a research team into a supernatural journey across the dark abyss of time - with history hanging in the balance. An investigation into a retired WWII sub plunges a research team into a supernatural journey across the dark abyss of time - with history hanging in the balance.