In "How the 'A' Stole Christmas", it was revealed that Sydney, along with Jenna, are a part of Alison's new group of followers. At the masquerade Ice Ball, Sydney reveals to Emily that she and Jenna believe Alison was the one who murdered Mona, though Mona turns out to be alive she still hates Ali.
In Season 7, Sydney returns to Rosewood, still working for Jenna, and now Uber A. She later meets with Aria, and tries to get her to join them, having joined herself because she "hates to be on the losing side".
Alex revealed that Sydney was a "one off" as she found out about her stealing from the bank she worked for and Sydney "fit the hoodie" for her plan against Aria.
Emily first notices Sydney staring at her by the staircase at Rosewood High and later again at the lockers. Thinking that she is staring because of Alison, Emily confronts her, only for Sydney to say that she admires her swimming talent and would love to hear Emily's opinions on her own swimming abilities. At first, Emily is hesitant, but agrees to help Sydney.
Having watched Sydney swim, Emily and Sydney head into the locker rooms, where Emily begins to measure Sydney's height to arm span ratio. Paige walks in and starts helping Emily, leading to an awkward conversation filled with suggestive innuendos.
Thrown From The Ride
Walking into the locker rooms from being in the pool, Sydney is disappointed in her 58 second time. Emily tells her that her technique is so much better and then asks if they want to meet up the next day. Sydney tells her she’ll have to ask her parents, but it should be okay. Emily explains that her mother keeps asking questions about Alison’s return home, and Sydney tells her it’s only natural and that she has questions too.
Sydney comes into the locker room and apologises to Emily for being late. Emily asks if Paige wants to join them, and Sydney backs her up, saying they’re only doing sprints on the track.
At the Pizzeria in town, Sydney, Emily and Paige are grabbing some food to eat.
Miss Me x 100
As Alison walks into school Paige tells Sydney she can't stay and she leaves.
In the locker rooms Sydney tells Emily that the school Glee club is sponsoring a Frozen sing along tonight, but Emily isn't interested. Sydney reminds her that there will be free pizza and Emily will avoid playing 20 questions with her mother. Emily agrees to go.
In the Rosewood High courtyard, Sydney and Emily are buying popcorn, when Paige says that Jenna is back and apparently Shana is dead. She explains to Sydney that Jenna is a blind girl who used to go to Rosewood High, and that her and Shana were dating. Emily is uncomfortable and explains to Sydney that Jenna and Alison hated each other and that she and the other Liars were drafter into their war.
When the Liars walk into the cafeteria at school, Mona and her army - including Sydney - confront the Liars, with Mona coming forward and exposing Alison's lie with a video that proves Alison slapped her.
Pulling up to a picnic ground, Sydney and Jenna step out of Jenna's car. Sydney comments on the mustang parked in front of them, and Jenna tells her that it used to be hers. Walking over to Mona, Sydney informs her that the Liars do not want things to go back to the way they were. Jenna says that they remember the way Alison treated them, like they were her dolls. Mona is happy to hear this and muses that maybe they can get rid of Alison. The three girls turn to look as a third car pulls up.
The Silence of E. Lamb
In the girls’ bathroom, Sydney walks out of a stall as Alison and Emily are talking. She introduces herself to Alison and compliments her scarf.
At her locker, Sydney tells Emily that someone left a rat in Paige's locker after practice. She says Paige was shaking all over. When Emily asks who did it, Sydney tells her no one has fessed up, and the coach wants a team meeting, but Sydney doesn't think it was someone on the Sharks as everyone loves Paige. Emily comments that she hasn't seen Paige yet, and Sydney says she doesn't think she came to school. As Emily walks up to Mona and asks what she knows about Paige's incident, Mona greets Sydney, and Sydney greets her back.
In the Brew, Sydney is standing behind Hanna in the line where she introduces herself and mentions that she’s having a hot date with her homework. After asking if Hanna’s on her way out, and Hanna saying that she just had dinner over at Emily’s, Sydney gets a whiff of alcohol from Hanna’s breath and asks if Hanna wants to sit for a minute. When Hanna tells her she doesn’t, she’s just going to head home, Sydney suggests that Hanna wait it out with her, they’ll split a Panini.
Sitting down on the couches, Hanna tells Sydney take she was right, melted cheese is the best booze soaker, before saying that she needs a napkin. 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. Hanna says that they were at Emily’s house when it happened, and when Sydney asks if she knew who ever lived in the house, Hanna tells her that their friend Toby grew up there with his stepsister Jenna. Sydney says that Jenna’s name keeps popping up, and that people seem to have a lot of beef with her, and when Hanna says that she has her own chock to grind, Sydney comments that someone thought her house would make a good barbeque pit. When Hanna says that she thought the whole time they were fighting someone else’s battle, Sydney asks whether if she’s ever wanted to make up with Jenna and quit fighting . Hanna tells her that there was always the possibility that they could have done so with Shana but after everything that happened in New York, it was just too late before correcting herself and saying Jenna's name instead.
Having grabbed some more coffee, Sydney says that if Hanna likes, they can take them to go, and she can drop Hanna off at home, but Hanna tells her she might walk home, the air may help. After asking if she’s sure, Sydney picks up her books and tells Hanna that she’ll see her at school before walking out.
Scream For Me
Sydney is changing in the Rosewood High locker rooms when Emily approaches her. Emily couldn't watch practice because she got hung up in the language lab. Sydney says she beat her personal freestyle record. Emily thanks Sydney for helping Hanna sober up the night before. She questions Sydney about what Hanna might've said and if she mentioned New York. Sydney says she didn't and wonders why Emily really came into the locker rooms. Sydney tells Emily the team wants her to be the assistant coach, but Emily says she already has a lot going on.
Walking into Emily’s bedroom, Sydney gives Emily the hooded sweatshirt and says she got ahead of herself. She explains that since they've stopped training together, Sydney 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. Sydney lets it slip that she knows Emily and her friends were in New York, but covers when Emily points out her lie by saying she must've been mixed up from too much time in the pool.
March of Crimes
Sydney walks into the Optometrists office with Jenna holding onto her arm.
Walking out of a consulting room and into the waiting room, Sydney and Jenna stop when Emily recognises Sydney. When Emily asks Sydney what she is doing at the Optometrists, Jenna explains that Sydney was her ride. Emily wonders when Jenna and Sydney became friends, and when Jenna tries to get Sydney to walk away with her, Spencer tells Sydney that Emily asked her a question. Emily asks Sydney why she never mentioned she and Jenna were friends, and Jenna comments that maybe it never came up, to which Spencer tells Jenna that maybe she should let Sydney speak for herself. Jenna asks Sydney if they can please leave, and when Emily tries to get them to wait. After questioning Spencer and Emily how long it is going to take to realise that they are nervous around the wrong person, she’s not Alison, Jenna links her arm with Sydney and the pair walk off.
Sitting in her car out the front of Emily’s house, Sydney gets out as Emily goes to get into her own vehicle. When Sydney asks if Emily has a minute, Emily questions why Sydney is parked on her street, and Sydney tells her that she wanted to explain. Emily asks if Jenna is hiding in the trunk, and Sydney pleads with Emily to let her explain. As Emily questions how she’s going to trust anything Sydney ever says again, Sydney tells her that she met Jenna a couple of years ago, and she used to volunteer at the school for the visually impaired, “I was there the day Alison came to visit Jenna and I pretty much glued Jenna back together when Alison left”. Emily comments that was a long time ago, and Alison has been through a lot since then, and Sydney mentions that “so has Jenna”. Going on, Sydney says that when Jenna heard that Alison was alive and coming home she panicked, “she felt totally alone so she reached out to me”.
Emily wonders what Jenna asks Sydney to do, apart from taking her to her doctor’s appointments, and shrugging, Sydney says Jenna wanted to feel safe, “I guess. Make sure that Alison…”, but cutting her off, Emily tells Sydney to forget Alison. Reminding Sydney that she latched onto her, Emily says that Sydney gave her gifts, took over her weekends with training and told her sob stories of how she had no one cheering for her in the bleachers. Sydney comments that she didn’t expect to like Emily, and when Emily questions her, Sydney shrugs, “I didn’t know you’d be such a decent person. I guess I was expecting you to be…” Trailing off, Sydney mentions that “this is so messed up”, and Emily tells her that it’s about to get a whole lot messier, she’s taking the coaching position just so she can be in Sydney’s face, watching her as much as she can. Emily goes on to say that she wants to see Sydney underwater long enough for her to feel that twinge of panic when she needs air and she can’t get it. Commenting that she wants Sydney to know what it feels like to be sucker punched, Emily gets into her car and leaves Sydney standing in the middle of the street, watching as she drives away.
How the 'A' Stole Christmas
Sydney is part of the school choir who are singing Christmas songs for Shady Days Nursing Home, along with Paige, Emily, Lucas and Jenna.
After Emily has said Merry Christmas to one of the Shady Days Nursing Home residents, Sydney approaches her, and asks if Emily’s got a minute. Emily questions what Sydney wants, and Sydney comments that it looks as though Emily and Paige worked things out. Emily then asks why Jenna doesn’t come over here and talk with her, and that Sydney doesn’t have to be Jenna’s eyes and ears. After Emily questions that Jenna can still hear, Sydney says that Jenna is not a bad person, “you just wouldn’t know that because Alison convinced you that she’s the enemy”. Emily asks if that’s all, and Sydney tells her that she just wanted to say Merry Christmas.
Unbeknownst at the time, Sydney is one of Alison’s followers as Alison makes her grand entrance at the Masquerade Ice Ball.
Still wearing a masquerade mask, Sydney and another of Alison’s followers, later revealed as Jenna, pose for a photo with Lucas, who is dressed as Santa Claus. Lucas tells the two masked beauties to come in closer, and after the photo is taken, he wishes them a Merry Christmas.
After gaining Emily’s attention, Sydney and Jenna begin walking through the crowd, with Sydney looking over her shoulder to make sure that Emily follows. As Emily enters the room which has been draped with long fabrics for privacy , Sydney steps up behind her, and tells Emily that she doesn’t have to be afraid, before taking off her mask and revealing herself. Sydney explains that she led Emily here because she doesn’t want Alison to see them talking. As Sydney walks towards the other masked follower, Emily tells Sydney that she really gets around, and questions if Jenna knows Sydney is with Alison now. The second masked follower takes off her mask, revealing herself to be Jenna. Sydney tells Emily that she promises that they’re not the enemy, but Emily says that they are sleeping with the enemy. Rolling her eyes, Sydney says that she’s “not gay”, and Emily says that’s not what she meant. Emily tells Sydney and Jenna that they think Alison killed Mona, and Sydney comments, “we do too”.
The DArkest Knight
She pretends to be Jenna while Caleb and Mona stake out the Radley. She gives them coffee and reveals herself saying the drinks are compliments of Jenna.
Hold Your Piece
She talks with Emily at an outdoor diner where she tells Emily she tried to distance herself from Jenna over the years. She did the coffee delivery without knowing that Noel and Jenna were intending to kill the girls. Later, she picks up a prescription for an "A.D." which leads Aria and Emily to plant a tracking device in her bag in hopes that she'll lead them to Jenna.
Emily reveals that Sydney played them and left the device on a greyhound to Philidelphia. She later reaches out to Aria on A.D.'s behalf to offer her a chance to join their team but only if she is willing to betray her friends. When asked why she did all of this, Sydney says it's better to be on the "winning team."