A small town is taken over by an alien plague, turning residents into zombies and all forms of mutant monsters.

When the renegade crew of Serenity agrees to hide a fugitive on their ship, they find themselves in an action-packed battle between the relentless military might of a totalitarian regime who will destroy anything - or anyone - to get the girl back and the bloodthirsty creatures who roam the uncharted areas of space. But, the greatest danger of all may be on their ship.