Doom 3 is more of a remake of the original then a sequel to the series. The game sees you take up the role of an unnamed Marine in the 22nd century. You have just been sent on assignment to the Union Aerospace Corporation"s Mars research facility. The facility has been rocked by a series of accidents, disappearances and generally strange things going on. When you are sent on your first assignment to track down a missing scientist who has fled to an old communications building all hell breaks lose, literally. Yes those good scientists from the UAC have unlocked the gates to Hell itself. It?s now up to you alone to figure out what exactly has happened and to stop the pure evil forces of hell reaching earth.