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Wanted
In the start of this book, Hanna, Aria, Emily, and Spencer are shocked to learn of the existence of Alison's twin, Courtney, when she's introduced at a press conference. When the unexpected twin is revealed, everyone believes that Ali is still alive. Courtney had spent her life in institutions due to "health issues" and her existence was kept secret by her family. She is finally released and goes home to Rosewood, where she attempts to resume her sister's life and begins tentative friendships with Ali's old friends. She later reveals that she's actually Ali; that the real Courtney had pretended to be her on the night of Ali's disappearance, and she was the one who was killed. She tells the girls that when she tried to tell her family who she was, they didn't believe her because Courtney was notorious for pretending to be Ali, and sent her back to the institution in Courtney's place. The girls are thrilled that Ali is back, and jump at the chance to go with her to the family's house in the Poconos after a school dance. On the way there Spencer gets a frantic call from her mother telling her that Melissa has disappeared. Spencer had begun to believe that her sister was the one who killed Ali and that she may be after the rest of them, but once they arrive at the house it's revealed that Ali is the killer. The girl they were friends with years ago was actually Courtney, and the real Ali was stuck in an institution. She killed Courtney for ruining her life, attempted to kill the girls in the forest fire, and is now going to kill them by setting the house on fire. They're able to escape after stumbling onto Ian's body hidden in a closet and releasing a bound Melissa, who Ali had kidnapped and was planning to kill as well. Ali is trapped inside the house and it's assumed she died in the fire, although her body is never found. The police discover that she killed Ian, Jenna, Courtney, and is "A". She did this all for revenge on them because they were all part of Courtney's life, which was supposed to be hers. After learning that her ex-husband shipped Hanna off to a mental institution, Hanna's mother transfers back to Rosewood and kicks Hanna's father, Isabel, and Kate out of the house, thrilling Hanna. Hanna and Mike get back together, and Meredith goes into labor, giving birth to a girl. Aria and Noel Kahn get back together after it's revealed that "A" kissed him, not the other way around, and Ella breaks up with Xavier after learning of his inappropriate behavior towards Aria. Spencer's father proclaims that even though he and her mother may not get back together, things are going to change for the better in their family, and Spencer and Melissa grow closer after almost being killed. Emily buries everything she can find that reminds her of Ali at Courtney's grave, hoping she can finally find closure, but is unsure of whether the noises she hears at the cemetery are real or imagined.
