"1. A string of violent murders has been happening within a small town, mostly being called "animal attacks".  Local law enforcement/rangers or even something higher on the command chain knows that it isn't being done by animal nor human.  Suspicion falls upon a drifter that showed up around the same time, but can they work together to keep the town safe?  (This idea can definitely expand into world building!)"

 
What if the animal turns put to be a zombie experiment?