Ohhh I just read a small spoiler...
Do the old Drag over Text to read It:
Spoiler Alert!
You start the game as a marine walking through a research outpost on Mars. "You don't jump into the action right away. As soon as you want to begin, you report for duty and go out on patrol," Willits says. Before long, a gateway to hell opens, leaving you as one of the few survivors. Ah, but seeing as how you played the original Doom, you already knew that. But did you know that there's an ancient civilization buried deep in the heart of Mars? Did you know that this had also happened centuries ago and the demons were beaten back with some ultimate weapon?
While the folks at Id didn't have any artwork to show of this nifty bit of alien gear, we can give you a hint: The new weapon, called the soul cube, has nothing to do with Hellraiser. This contraption, though, was powerful enough to beat back the demonic hordes once. Realizing its power, the hordes grabbed it and brought it back to hell to make sure it couldn't be used again?which means you're going to have to go down into the bowels of the underworld, where this superweapon is being guarded, retrieve it, and stop the inevitable invasion of Earth. OK, end of spoiler.
End Spoiler.
Stephen