Alison is the former leader of Rosewood's most exclusive middle school clique. Before her disappearance, she held immense power over her friends by hoarding their deepest insecurities and using that knowledge to manipulate them. Three years after she goes missing, the discovery of her buried body forces her former friends to confront the traumatic past they share.

Aria is an artsy teenager trying to reconcile her confident European persona with the awkward girl she used to be. She carries heavy guilt over witnessing her father's infidelity, a secret she actively hides from her mother. Desperate for a fresh start, she illegally drinks at a local bar and initiates a connection with a young man who turns out to be her teacher.

Emily is a highly obedient daughter and a star competitive swimmer facing intense pressure from her parents. Though she has a boyfriend on the swim team, her world shifts when she befriends the relaxed, rebellious new girl in town. She carries guilt over her past devotion to Alison and begins questioning her own sexuality.

Spencer is a wealthy, hyper-competitive student who lives next door to Alison's former home. She constantly battles her older sister for their parents' approval, striving for perfection in academics and sports. Her rivalry escalates drastically when she develops a mutual attraction to her sister's new British boyfriend.

Hanna is the formerly overweight, insecure girl of the group who transformed into a model-thin, popular student after Alison's disappearance. She engages in reckless behavior, including theft and drunk driving, to cope with her father's rejection and his new picture-perfect family. She desperately hides the return of her eating disorder while trying to maintain a flawless public image.

Mona is a formerly unpopular student who bonded with Hanna over losing weight and ascending the social ladder. Now highly sought-after, she encourages Hanna's illicit behavior and often acts as a willing accomplice in her crimes. She serves as a substitute for Alison in Hanna's life, demanding loyalty and projecting intense confidence.

Melissa is Spencer's older sister, an overachieving Penn graduate preparing to attend Wharton. Prim, proper, and seemingly flawless, she constantly outshines Spencer, fueling a bitter sibling rivalry. She brings her new medical student boyfriend to Rosewood, inadvertently setting the stage for a destructive family conflict.

Ezra is a recent college graduate with a charming demeanor who connects instantly with Aria over their shared interests. The romance complicates rapidly when he is revealed as the new English teacher at Rosewood Day School. He tries to establish professional boundaries but struggles to stay away from his student.

Wren is a medical student from London with a charming British accent and a relaxed attitude. He stands out from the predictable, textbook boys Melissa usually dates. He develops a quick, flirtatious connection with Spencer while staying at the Hastings family barn.

Maya is a new student who moves into the DiLaurentis property. Tall, skinny, and relaxed, she openly smokes weed and has a casual family environment. She quickly befriends Emily, gently encouraging her to break strict rules and explore her hidden feelings.

A is a mysterious, anonymous figure who aggressively stalks Aria, Emily, Hanna, and Spencer. Communicating via texts, emails, and notes, A demonstrates intimate, impossible knowledge of both the girls' seventh-grade secrets and their current illicit behaviors. A uses this information to manipulate, threaten, and terrorize the group.

Ian is Melissa's high school ex-boyfriend who recently returned to Rosewood as the field hockey and lacrosse coach. Handsome and athletic, he is a living reminder of the time Spencer secretly kissed him to score points against her sister.

Andrew is the class president who defeated Spencer in the school election. With his neat appearance and clean reputation, he initially seems innocent, though Spencer briefly suspects he might be spying on her. He demonstrates quiet kindness during a moment of profound shock.

Jenna is a former classmate and neighbor of Alison and Spencer. She lost her vision permanently due to a prank orchestrated by Alison, an event the girls refer to in hushed tones as "The Jenna Thing." Her continued presence in Rosewood is a terrifying reminder of the girls' past cruelty.

Toby is Jenna's brother and the original intended target of the prank that blinded his sister. He witnessed Alison observing the accident but remains entirely silent because Alison caught him doing something equally shameful on the same day.

Byron is Aria's father and an art history professor. He moved his family to Iceland for his academic research, but underneath his intellectual exterior lies a damaging secret: an affair with one of his former students that Aria accidentally witnessed.

Ella is Aria's mother. She is completely unaware of her husband's past infidelity, an ignorance that creates an underlying tension in her relationship with her daughter, who carries the heavy burden of the secret.

Mike is Aria's younger brother. Unlike Aria, he is thrilled to return from Iceland to Rosewood and quickly integrates into the local athletic and social scenes, observing his sister's shifting behavior with mild suspicion.

Ben is Emily's boyfriend and a fellow member of the high school swim team. He becomes aggressive and highly possessive, reacting poorly when Emily starts spending less time with him and more time exploring her new connection with her neighbor.

Sean is Hanna's seemingly perfect boyfriend. He shocks Hanna by joining a virginity club and refusing her sexual advances, leading to a dramatic, humiliating rejection at a high school party.

Darren is a young Rosewood police officer and former local student who catches Hanna shoplifting and later detains her for a drunk driving accident. He handles her legal troubles in a highly inappropriate manner through a private arrangement with her mother.

Kate is the beautiful, graceful daughter of Hanna's father's fiancée. Her flawless appearance and the preferential treatment she receives from Hanna's father severely trigger Hanna's deep insecurities, sparking a severe eating disorder.

Noel is a popular, wealthy boy at Rosewood Day School who plays lacrosse and hosts massive parties on his sprawling estate. He shows consistent interest in Aria, though she mostly uses his attention to make her teacher jealous.