After the fire, no one believes the girls when they insist that they saw Alison. "A" sends Emily to Lancaster, where Emily comes to believe Wilden is Alison's murderer. Aria begins a relationship with Noel Kahn, after he defends her at a party. She visits a medium, who produces a message in Ali's handwriting that states that "Ali killed Ali."
Hanna's father sends her to a clinic to prevent her eating disorder from reappearing due to stress, where she befriends a troubled girl named Iris. Hanna has more dreams about Ali, which causes her to suspect that Iris had something to do with Ali's death. "A" reveals to Spencer that her father had an affair (and that Alison is Spencer's half-sister), making her suspicious of her mother.
The Liars are arrested for Ali's murder. They realize that "A" has tricked each of them into believing someone else killed Ali. However, a man named Billy Ford is soon arrested for murdering Alison and Jenna Cavanaugh. No one now believes Ian was alive.