You, a normal marine, have just been transferred to a facility on Mars for extra security.
Unknown to you, strange things have been going on. Lights constantly flicker, and people claim to have heard voices.
Not to mention the constant transfers whenever somebody gets too nosey.
But when you are told to find a missing scientist, you also find out what's really going on: a teleportation project, which opens a portal to Hell.
Now, with the base overrun by zombies and demons, you must fight your way for survival and attempt to get help...if there's anything left of you TO help...