Heartless

Heartless is the seventh book in the series Pretty Little Liars by Sara Shepard, which was published on January 19th, 2010 by HarperTeen.

Book Summary
After the fire, no one believes the girls when they insist that they saw Alison DiLaurentis, and they start to believe it was all a hallucination due to the smoke. "A" sends Emily Fields to Lancaster, where she discovers that an Amish girl named Leah disappeared around the time of Ali's death. Emily also discovers that Darren Wilden had been Amish and left the community, and she soon comes to believe that he killed Leah. Thinking that Ali's ghost is trying to tell her something, Aria Montgomery goes to a séance; she learns nothing, but meets Noel Kahn. She initially does not trust him but later changes her mind, kissing him after he comes to her defense at a party. Aria sees another medium, who produces a message in Ali's handwriting that says "Ali killed Ali". Hanna Marin's father sends her to a clinic to prevent her eating disorder from reappearing due to stress from the Ali situation, and to cure her Post traumatic stress disorder. Hanna befriends another patient named Iris, who later abandons her after another patient reveals Hanna's scandalous past to everyone at the clinic. Hanna has more dreams about Ali that are similar to the ones she was having while in her coma and later on, who leads her to suspect that Iris had something to do with Ali's death. "A" sends Spencer Hastings messages which make her suspicious of her mother; Spencer learns that at one point her father had been having an affair with Ali's mother. Spencer realizes the possibility that Ali and Jason are her half-siblings, and is led to believe that her mother may have killed Ali because of it. Spencer confronts her parents, but her mother is shocked to hear about the affair for the first time. Aria, Spencer, Emily, and Hanna are all arrested for Ali's murder; together in a jail cell, they realize that "A" has tricked each of them into believing someone else killed Ali. Wilden releases the girls and tells them that Billy Ford killed Ali; Emily recognizes him as one of the men working on Ali's gazebo. Billy is also charged for Jenna Cavanaugh's murder, and the reader is left wondering whether Billy was "A" or not.