You've obviously never met my great uncle Stan. He lied to everyone about who he was for, like, thirty years.

[...context--nope, moving on]

But we don't have several weeks. People are already being murdered! If we can't find out who's doing it, we're all just going to be picked off one by one. Or more-- if they think they can get away with it, why limit themselves to one? We need a way to figure people and roles out, and fast.