Hanna's new interest in crime novels helps her to come up with a plan to try and figure out whose body is in Ali's grave. While Hanna is on her hunt, Spencer is working overtime to decipher the stories in Ali's diary which she hopes will reveal the identity of Ali's mystery man. But with both girls hot on the trail, will their work lead them straight into "A's" path?
Meanwhile, Aria is upset with the new friend Mike has made and Emily's dad is concerned about her behavior.
Never trust a pretty girl with an ugly secret. Gossip thrives amid the Mercedes-Benz, mega mansions, and perfectly manicured hedges in the exclusive town of Rosewood, Pennsylvania. Everyone has something to hide. Based off the book series of the same name, the series follows four estranged best friends Spencer, Hanna, Aria, and Emily who are reunited after their best friend and queen bee of the group, Alison, goes missing only to discover they are receiving messages from an anonymous "A" who knows all their secrets.