Based on the Pretty Little Liars series of young adult novels by Sara Shepard, the series follows the lives of four girls — Spencer, Hanna, Aria, and Emily — whose clique falls apart after the disappearance of their queen bee, Alison. One year later, they begin receiving messages from someone using the name "A" who threatens to expose their secrets — including long-hidden ones they thought only Alison knew. The show stars Lucy Hale and Holly Marie Combs In the series finale of Pretty Little Liars, all is revealed as the ultimate endgame comes to light. Convinced they know who A.D. is, the Liars gear up for a confrontation. Spencer, Hanna, and Caleb team up to investigate and discover new information about Charlotte’s death. Meanwhile, Mary Drake returns with a gift for Spencer and Alison. The Rosewood PD turn up the heat on the Liars, causing loved ones to try and close ranks. Aria’s recent collaboration with A.D. comes to the attention of a surprising source. A.D. presents the PLLs with a choice designed to drive a wedge between them. Meanwhile, everyone tries to find a bit of happiness before all hell breaks loose. Toby returns to Rosewood, and Aria makes a horrifying discovery. With Mona making inroads in the game, Emily reluctantly teams up with her to investigate. Ashley returns to Rosewood to check on Hanna after learning some frightening information and asks Caleb what his intentions are with her daughter. Meanwhile, Spencer’s family reels from A.D.’s latest taunt, leaving Spencer more confused than ever about who to trust. Ezra notices Aria’s change in attitude and fears he may have lost her; and A.D.’s machinations cause Aria to have a terrifying nightmare. As Detective Furey closes in on uncovering what happened to Archer Dunhill, the Liars team up to protect one of their own. Hanna continues to struggle with the idea that Lucas might be connected to A.D. even in the face of more evidence. Emily surprises Ali with a heartfelt gesture that is undone by A.D. machinations; and the Liars gain insight into where the idea for the game originated.