This is a Dark Ride
In this special Halloween episode (which is a homage to teen slasher horror flicks such as Halloween and Terror Train among others), the Liars are unable to enjoy the festivities for a Rosewood train excursion when it becomes apparent that “A” is on the train and out for blood. Adam Lambert performs live. Someone disguised as the Queen of Hearts spikes Aria’s drink while she sits and rests in-between Adam’s sets. Garrett corners Spencer and reveals to her that he made Jenna think that he killed Alison, but it was a ruse. Garrett also mentions he overheard Alison and Byron having a conversation in her backyard and Alison was blackmailing Byron. Hanna dances with a masked figure she believes to be Caleb, but eventually realizes it isn’t him – this person is later revealed to be Mona, who has evidently snuck out of Radley. Spencer tells Garrett to stay put while she goes to retrieve Aria for Garrett to tell her this information. Unfortunately, Aria is nowhere to be found. Paige, Emily, Hanna, Caleb, Spencer and Toby search the train for Aria. It is revealed to the home viewers that Aria is bound and gagged with duct tape, is trapped in a box with the now dead corpse of Garrett Reynolds. As the search progresses, Spencer is attacked by a someone wearing a queen of hearts costume. The Queen of Hearts almost chokes Spencer to death, but Paige thwarts off this mystery attacker. Spencer thanks her. We hear voices as the box Aria is trapped in is pushed towards the edge of the train. Aria stabs someone with a screwdriver she finds in the box. She is soon after rescued by her friends. When the train stops, Noel and Toby fight and Toby pushes Noel against a prop casket. The casket is knocked over and a body bag covered in ice spills out. The final scene shows a flashback of the night Alison died, showing the construction of her backyard, the place Alison was buried alive. Moments later, a hand comes out of the ground, wearing a purple string bracelet, attempting to get out.