'A' has always had fun playing with the liars, but now they have the biggest game to date in store for the girls.
- We open with the girls on their way to prison. Hanna tries to prepare them for what to expect. Suddenly the vehicle stops and a shadowy figure appears at the back. The person fires some type of gas into the vehicle and the girls are knocked out.
Toby tells Spencer's parents that the girls are missing. The deputies were drugged and have no memory of what happened. Tanner wants to keep the who thing secret, including from the other three girls' parents.
The girls each wake up in separate, locked bedrooms. Video cameras watch them from the ceiling. Spencer breaks a window but finds a solid wall behind it. The doors open and they are guided down a pathway to a room where Mona (gasp!) is playing the piano. She's dyed her hair to replicate Alison's look. Mona, who seems especially crazy, tells the girls that Mrs. Grunwald saved her life and doesn't let them call her Mona. In another room Mona, who seems to respond to chimes like an automaton, has them start playing the Mystery Date board game. It is to figure out their prom dates. It seems as if Mona is also being held prisoner.
Caleb and Ezra come up short trying to find an image of A during the girls' abduction.
Mona tells the girls each night there is a three-minute window while the power generator re-boots. She's yet to find a way out. She is herself, only pretending to be crazy while "it" is watching. If they don't return to their room in time they're left in the hallway for days.
Spencer's parents confront Alison in prison. They tell her about the girls being missing and she seems devastated. She says she knows A took them and that Mona isn't A.
Somebody is watching live video of the girls from a control room of some kind. Spencer has a dream where she sees the name "Charles." Mona wakes up and finds a gas mask from A in a box, "because you're my favorite."
Toby brings information of the police van being cyberhacked to Tanner. She's gotten similar info from her staff and proceeds to put out an APB on Caleb. She thinks he knows where Hanna is located.
The girls are given "jobs" putting together a prom that seems to be from seven years earlier. Secretly Mona tells them about the mask.
Toby, Caleb and Ezra talk to Spencer's parents about A and the issues with Tanner. They agree to help the guys dig. The police arrive and Caleb quickly turns himself in to protect Toby. Melissa calls and we see that Andrew is listening in.
That night the girls talk about their plan. Using materials they say are for the "prom," Spencer should be able to temporarily shut down the power. The next day they stage an argument in order to distract the camera and allow Mona to set a few things aside. The plan is to stage a photo when A enters the prom. The "camera" will trigger the device.
Caleb and Spencer's parents are able to convince Tanner to let Caleb have access to the police system so he can track down A. He's quickly able to pinpoint a GPS coordinate for the van.
A's "prom" gets underway. The room is filed with masked mannequins, but it looks like A is one of them. Mona arrives at the top of the stairs wearing her A mask. The girls are able to talk "Charles" into joining Mona and be king. Aria snaps the photo and the power goes down. All five immediately make a break for it.
Spencer's parents arrive and recognize the van is near an old candle farm where their families would go apple picking. The police enter a cellar door and find A's command center.
The power comes back on and Spencer finds herself in a room with a camera. She puts on what look like home movies at the factory. A walks in behind her but leaves when Mona arrives.
Tanner and Toby watch videos from A's cameras, but can't figure out the location where the girls are being held.
The girls now find themselves outside, surrounded by electric fencing.