After analyzing, we've found it very well could be Alison guilty of killing Mona. It is just so hard to believe that she is capable of that. Then, I noticed that the hair looks slightly blonder (not sure if it's the lighting or not). Courtney DiLaurentis, is that you? I know that they said they wouldn't go with the twin theory, but why would they tell us if they were? One thing is certain, that's not a wig. Perhaps CeCe is making a comeback to protect Ali even.