Bigby theory (spoilers)
maybe the disappearances of Snow, Faith, and anyone else that ends up "dead," get pinned on Bigby when accused by "The boy who cried wolf." The accusation ends up making the town's people to believe that Bigby is the murderer, when they aren't actually dead. Bigby could then be cleared of the murders in episode 4, (Wolf in sheep's clothing.) This may enrage Bigby, into committing murders himself, and when he is caught by one of the fables, (maybe the boy who cried wolf again?) nobody believes him due to the previous accusation. (episode 5: Cry Wolf) The picture of episode 5 shows Bigby in wolf form with blood on his claws.