one day the world was changed when the dark rain happened everyone caught in it was changed turned into flesh craving hords of the undead

the human colony ship Zion travels through the galaxy searching for a place where humanity can have a second chance a future once one of many now possibly all that is left of the human race one of the life lines for the final ship of humanity is the ARST advanced recon scout teams these elite units are sent to investigate possible habitable worlds