Hanna has some explaining to do to her parents and the police after she's found with something she shouldn't have. Mona spills a secret of Spencer's to the other Liars - leading to hurt feelings amongst the group. Emily tries to help Hanna, only to have "A" turn the tables. And Aria helps out a friend of Mike's, who gets the wrong impression of her.
Meanwhile, Shana keeps popping up in the most unusual places. And Spencer's investigation into who was on the other end of Ali's mysterious phone number leads her and Toby to Ravenswood - which is unlike any place they've ever seen.
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.