Unbelievable

Unbelievable is the second book in the series Pretty Little Liars by Sara Shepard, which was published on May 27th, 2008 by HarperTeen.

Hanna survives but has no memory of who "A" is. Sent to live with her strict aunt and uncle in Iowa after the "gay away" program fails to turn her straight, Emily meets a girl named Trista and eventually runs away. Ezra has moved after avoiding formal charges, forcing Aria to move in with her father. Emily sees her parents on the news telling her to come home; after doing some thinking, they are now willing to accept her for who she is, even welcoming Maya. Spencer and Mona plan a party for Hanna's return to Rosewood Day, and Mona reveals that she has received messages from "A" as well. Spencer begins to suspect that Melissa is Ali's killer. Recovered from her injuries, Hanna starts dating Lucas again. Despite Lucas' warnings of Mona's bad intentions, Hanna breaks up with him in part due to Mona's interference. At Hanna's party, Maya catches Emily and Trista kissing and runs off. The girls are set to turn in Melissa to the police for Ali's death; at Mona's insistence, Emily and Hanna wait at the party while Spencer and Mona drive to the police station. Something Emily says triggers Hanna's memory of her accident, and she suddenly remembers who "A" is — Mona. Telling Spencer they are going to a police station, Mona actually takes her to a mountain cliff and tries to push Spencer off. Spencer moves aside, and Mona falls to her death.