"The Darkness?" "The Empty?" Someone give the writers a theraurus for thinking up names...

Sam is actually the only soulless person who didn't go completely nasty--remember the townfolk in the flashback ep with Josei and Henry, they all went murderous too.

And someone did write the boys in the car in the way back to the bunker:
https://www.fanfiction.net/s/11561420/1/