Perfect!

      The night that Ali died, she was hypnotizing Emily, Spencer, Hanna, and Aria. Ali and Spencer got into a fight and ran out of the barn. Spencer came back alone and worried, and Ali was gone.

     But what else happened that night? There is a blacked-out spot in Spencer's mind. She keeps getting weird flashbacks to a forgotten fight with Ali. Spencer's therapist says that Spencer blacked the time out on purpose, but there is a way to remember it.

     All four girls figure out who the murderer is at the same time.
   


     TBR: The rest of the Pretty Little Liars series (five books I can't remember the titles of)