A group of space colonists from the Aegis VII colony fight against the infection of Necromorphs created when the Red Marker was removed.
Did You Know?
In Chapter 5, someone asks if any escape pods were left on the Ishumura and the player is told all the escape pods launched empty already. However this is not possible, since in Dead Space (VG) which takes place immediately upon the end of this game, an intact escape pod is still on board the ship not too far from the bridge. It's the pod that Hammond launched with a necromorph inside it. See more
So aliens do exist.
And they're trying to kill us. Isn't life dandy...