Driscoll is introduced as a false protagonist, only to be exposed as a member of Mona's army and a close friend of Jenna Marshall.
Driscoll initially appears to be a sweet and soft-spoken student with an identity crisis,[6] although she's later revealed to be working against the Liars.
In the Rosewood High courtyard, Sydney and Emily are buying popcorn, when Paige divulges that Jenna is back in town and Shana is deceased.
During their meal, Sydney lifts a newspaper that has the Cavanaugh house explosion on the front, and mentions to Hanna that she was just reading about what happened.
Emily couldn't watch practice because she got hung up in the language lab before thanking Sydney for helping Hanna sober up the night before.
She explains that since they've stopped training together, Driscoll just wanted to have someone in the bleachers cheering for her, since her boyfriend is off in college and her parents aren't into it.
Later on the episode, Driscoll reveals to Emily that she met Jenna when she volunteered at a school for the visually impaired and have remained friends ever since the day Alison visited Marshall to threaten her.
Still wearing a mask, Jenna and another one of Alison's followers, later revealed as Driscoll, pose for a photo with Lucas, who is dressed as Santa Claus.
In "The DArkest Knight", Mona and Caleb manage to bug Jenna's cellphone and eavesdrop a voice message she left for Noel after he failed to return any of her calls.
Once Hanna successfully fabricates a story to the police on how she went to Hollybrook to track down the girl Kahn pushed down a flight of stairs at a frat party, Mona purposely bumps into Marshall at The Radley.
Nonetheless, Jenna manages to trick the duo after hiring Sydney to pose as a decoy and serve them coffee in order to buy Marshall sufficient time to track down the Liars at gunpoint at an abandoned school for blind students.
After searching her name online, they discover that Driscoll graduated from Berkeley College, with a double major in Economics and French.
Sydney currently resides in a loft at Fishtown, Philadelphia, whilst working as a bank teller at a private department that services extremely wealthy clients.
The girls also learn that Sydney checked into a charity gala for the Manhattan Children's Hospital, the same ball where Katherine made an appearance wearing Hanna's dress.
Following this enlightenment, Emily googles the event and comes across a picture of Daly posing on a red carpet whilst Driscoll sneakily uses a phone to photograph her dress.
They conclude Driscoll most likely made adjustments for Marshall to be clothed in a duplicate of Hanna's dress so Jenna could omit the truth from the authorities.
Following a quick lesson from Caleb on spying techniques, Aria instructed Emily to approach Driscoll and clone her phone.
Through access to Driscoll's phone, the girls discover that Sydney had an appointment at the Vogel Vision Institute and eavesdrop the meeting.
Turns out Driscoll was paying for an operation to give Jenna her sight back and she uttered the initials "A.D." as the donor for the cost.
The mysterious entity divulges to Aria they own a stolen file from Jessica DiLaurentis' burnt lair at Carol Ward's storm cellar containing information that could send Ezra to jail.
Abruptly, the game phone starts making a quacking sound in Ali's purse, which confuses the two girls momentarily until Aria spots a nearby store called the Darling Duck.
Aria begins to question her about of all of the things she had done to them, namely shooting Spencer, helping Jenna escape, and creating the board game.
When Aria questions Sydney's motives for being on the A-Team, she explains that working for their enemy means being a part of the "winning team".
De Elizabeth from Teen Vogue was particularly favorable towards the scene when Sydney offers Aria Montgomery a chance to work with the Liars' tormentor.