You get to play from the zombies' point of view /facepalm didn't you know?
Character #1: Billy
He looks like a hillbilly zombie, he wears a straw hat and says some things like "I'm killin' more humans than a rattlesnake kills mice in a cornfield."
Character #2: Samantha
It's that little girl, she's a zombie now =D. So basically you get to see a little girl run around and kill humans.
And from those two, the other two aren't that hard to figure out
Okay, but really, I hope it's not the normal 4 people, Richtoffen, Takeo, Dempsey, and Nikolai.