The player once again takes the role of the Marine, an unnamed hero, who, after being stranded on Phobos and subsequently fighting his way out of Deimos and Hell itself, returns back home to Earth — only to find that it too has fallen victim to an invasion from Hell.
With all the major cities in the world in ruins, the remaining leaders plan to use spacecraft to transport the survivors of Earth’s population. However, the starport is the only way for the ships to depart and the demons have protected it with a force field. All of humanity’s remaining soldiers make a desperate assault on the starport, but eventually, they are decimated and only the player remains.
Original title Doom