Hanna worries that her mother is keeping a dangerous secret and is determined to protect her at all costs, which leads her to an uncomfortable meeting with Detective Holbrook. A clue in Ali's things leads the Liars to a creepy mask maker, who takes a shine to Emily and may have ties to another Rosewood resident. Spencer and Toby continue their search into a painful chapter of Toby's past and Melissa returns to Rosewood.
Meanwhile, A targets Emily's mom, leading Aria to make a desperate plea of Ella.
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.