They've been abducted by aliens.
The town is the second (or third) iteration of The Village.
It's all a variant on the Milgram Experiment.
They are in Purgatory.
It's all an elaborate revenge game by someone with a lot of resources, even more anger, and still more patience.
There's two groups. One is the whole conspiracy, the other is a group within it that's rebelling.The guy that rescues Renby and Kat is also the guy that tried intimidating Renby in the first place (if this troper isn't mistaken).
Charlie didn't murder his wife. He just wanted Bill to get off his back.Bill being... Bill, Charlie probably thought that the only way to get Bill to stop is to scare the guy into being a Jerk Ass somewhere else. So while he did Mercy Kill his wife, he didn't outright kill her.
The process (to use Tom and Joe's term for lack of a better one) is to test people for mental fortitude in order to fight some bigger hidden threat.Having a CEO and an Ambassador's Daughter and others on your side would be useful. As well, Tori was eliminated after, essentially, breaking down.