A best-selling series of young adult thrillers, Pretty Little Liars follows four high school girls—Spencer Hastings, Hanna Marin, Aria Montgomery, and Emily Fields—whose clique falls apart after the mysterious disappearance of their queen bee leader, Alison DiLaurentis. Three years later, the four girls start receiving strange text messages from someone who refers to themselves as "A." The texts threaten to reveal the girls' deepest secrets—things they thought only Alison knew.
Published in 2006, Pretty Little Liars launched the series and marked Sara Shepard's debut as a YA author. The novel is loosely based on Shepard's experiences growing up in a suburb of Philadelphia, although, thankfully, she says she never had a serious stalker issue. After the success of the first book, Pretty Little Liars expanded into a 16-book series with two companion novels.
The novels cover serious subjects, including bullying, underage drinking, infidelity, eating disorders, mental health challenges, unexpected pregnancy, death, violence, and murder. The series is divided into four story arcs, each consisting of four books. Each arc chronicles the story of a different "A." Throughout, Spencer, Hanna, Aria, and Emily get into trouble because of their unwillingness to own up to the truth.
Warning: The following article contains spoilers for the Pretty Little Liars series.
Who are the main characters of Pretty Little Liars?
Spencer Hastings
Spencer Hastings is the overachiever of the group. She's highly competitive and constantly striving to be the best at everything she does, from aiming to be named valedictorian of her class to standing out as the star player on her field hockey team. She comes from a prominent and wealthy family that has lived in Rosewood for ages and is well-known in the community. Her family tends to pay more attention and give more favour to her older sister Melissa, which frustrates Spencer. Spencer is tall and slender and dresses in a preppy style. In the books, she's described as having wavy blond hair, blue eyes, a small upturned nose, and a pointed chin.
Hanna Marin
Hanna Marin is one of the most popular girls at school—but behind closed doors, she struggles with an eating disorder. She's highly insecure about her appearance and worried about what others think of her, especially because she used to be heavier when she was younger. Hanna is impulsive, flighty, and can be a bit of an airhead. Her parents are divorced, and she does not get along with her stepmother or her stepsister. Others see Hanna as extremely beautiful. She has long dark auburn hair and hazel eyes.
Aria Montgomery
Aria Montgomery is the artsy girl at school that some people call "weird," but that doesn't really bother her. Aria is bubbly, independent, and prefers to march to the beat of her own drum. She's a vegetarian, loves art, loves making short films, and loves to travel. Just like Aria doesn't quite fit in at her high school, her family is seen as odd in Rosewood. After Alison's disappearance, Aria moved with her family to Iceland for three years. Aria is described as having shoulder-length black hair and blue eyes. She is tall with a thin, dancer-like physique.
Emily Fields
Emily Fields is the shy girl of the group, and also the sweetest. She's highly empathetic, compassionate towards others, and very forgiving, often to a fault. She loves with her whole heart, and sometimes that love blinds her and makes her a bit naïve. Emily is bisexual, which her family doesn't want to accept at first, but they eventually come around. Competitive swimming is a huge part of Emily's life. In fact, she swims so much that her strawberry blond hair is usually slightly greenish from all the chlorine. Muscular from her athletic lifestyle, she has a freckled face and green eyes.
Alison DiLaurentis
Alison DiLaurentis was the most popular girl at Rosewood Day middle school until she went missing. At the beginning of the Pretty Little Liars series, everyone thinks they've found Alison's body and that she is dead. But the truth is much more shocking. Alison actually had a secret twin sister with whom she switched places and eventually killed. Alison was always the mean girl at the middle school, and she's a very vengeful person with a manipulative personality. Alison has wavy, honey-blond hair and blue eyes. Currently in the series, her hair is dyed brown to hide her identity.
What happens in Pretty Little Liars?
Arc 1
The first novel introduces high school juniors Spencer, Aria, Emily, and Hanna. Each girl has her own secrets. Spencer is developing feelings for her sister's boyfriend. Aria is having an affair with her English teacher, Ezra Fitz. Emily has a crush on the new girl at school, Maya St. Germain. And Hanna might be the popular girl at school, but she's secretly shoplifting and struggles with an eating disorder. When the girls start receiving texts that threaten to reveal their secrets, they all believe it could be Alison, their friend who went missing three years earlier while they were all at a sleepover together. So when Alison's corpse is found buried underneath the gazebo at her former house, the girls are shocked. The novel ends with all four of the liars receiving a text at Alison's funeral saying, "I'm still here, bitches. And I know everything. -A."
In the second novel in the series, A continues to harass the "Liars," Spencer, Aria, Emily, and Hanna. A threatens each of the girls separately that she will reveal their secrets if they don't do as she says. The Liars try to keep their secrets hidden and do as A says while also trying to uncover their harasser’s identity. Things come to a head at a charity dance party, where the girls are certain A is in attendance. Spencer becomes convinced that Toby is A, and after Emily spends time with Toby, she becomes convinced that he's the one who killed Alison. Before they can act on their suspicions, however, Toby commits suicide. Emily gets final proof that Toby was not A: another message from A telling her it isn't over until she says it is.
After Aria falls out with her family at the end of Flawless, she's left homeless and goes to live with her boyfriend, Sean. Aria is still seeing Ezra, however, but that relationship ends when Sean informs the police. Emily wants to go to the police about A, and in response, A outs Emily to the whole school. Meanwhile, Spencer comes to terms with the fact that she suffers from blackouts and fears that she might have been the one to kill Alison. After Hanna and Mona get into a fight, Hanna finds comfort with an "uncool" boy named Lucas. Then, she receives a text from A and recognizes the number. But before Hanna can reveal A's identity, A runs her down. The novel ends with the Liars getting a chilling text: "She Knew Too Much. -A."
Due to a head injury, Hanna loses her memory and no longer knows the identity of A. Emily's family finally comes to terms with her sexuality, but just as her relationship with Maya is falling apart. Aria takes an art class with Jenna and starts to suspect that she could be A. Meanwhile, Spencer is still worried that she's the one who could have killed Alison, but then becomes convinced that it was actually her sister Melissa's doing. When Hanna's memory finally returns, she realizes that her friend Mona has been A all along. Mona tries to convince Spencer to turn Melissa over to the police for killing Alison, but then Spencer gets a text from Emily, telling her that Mona is A. Mona reveals that she first planned on framing Spencer for Alison's death, but then she decided to frame Melissa instead. Mona tries to convince Spencer to become A with her. A fight breaks out between them, ending with Spencer accidentally pushing Mona off a cliff to her death.
Arc 2
It's a new arc in the Pretty Little Liars series, and a new A has surfaced. Now the girls are convinced that Ian is really Alison's killer, but he denies it. Emily finds herself falling for a boy, a Christian singer named Isaac. Hanna's rivalry with her stepsister Kate Randall is heating up. Aria develops feelings for a man she met at an art show—who winds up dating her mother. And Spencer begins to suspect that she's adopted. At the end of the novel, the girls find Ian's body in the woods behind Spencer's house. When they return with the police, the body is missing.
It looks as if yet another person has been framed for Alison's death—Ian is not the killer. The girls start wondering what the new A's intentions are. Does she really want to harass them, or does she just want to solve the mystery of Alison's death? After discovering that Jason DiLaurentis, Alison's older half-brother, was a patient at Radley Sanitarium, Hanna, Aria, and Emily now think that Jason had something to do with Alison's death. Aria sees a fire behind Spencer's barn and notices someone trapped by the flames. She comes to the rescue and makes a shocking discovery: it's Alison.
The Liars all insist they saw Alison in the fire, but no one believes them. A sends Emily to Lancaster, where Emily comes to believe that Alison was not the girl they found underneath the gazebo. Aria goes to see a medium, who gives Aria a message from Alison that says, “Ali killed Ali." Hanna's father sends her to a clinic out of fear that her eating disorder is coming back. There, Hannah meets a girl named Iris and becomes convinced Iris had something to do with Alison's death. Spencer discovers that her father had an affair, and Alison is actually her half-sister. By the end of the book, Spencer, Hanna, Aria, and Emily all realize that A has forced each of them to believe that a different person is responsible for Alison's death. Ultimately, a man named Billy Ford is arrested for murdering Alison.
In the final book in the second arc, the Liars are shocked to discover that Alison had a twin sister. Named Courtney, Alison's twin has spent the majority of her life in a mental health facility, and her family has kept her existence a secret. Jason DiLaurentis was never a patient at Radley—he was visiting his sister there. "Courtney" later reveals to the girls that she's actually Alison. The real Courtney pretended to be Alison on the night of her mysterious disappearance, and Courtney was the one who was killed. Alison tried to tell her family who she was, but they didn't believe her and sent her back to the institution. But the twists keep coming: it turns out Alison switched places with Courtney long ago, and it was actually Courtney the girls befriended years ago. Alison is the real killer...and now she's out to kill the rest of the girls. They are able to escape. At the end of the novel, it's assumed that Alison died when the house set on fire, but her body was never found.
Arc 3
Twisted
When the four Liars are vacationing in Jamaica together, Emily sees a girl she suspects might be Alison. As details of what happened on that trip to Jamaica are slowly unraveled, it’s revealed that the Liars "got rid" of the girl they believed to be Alison. Then, the girls start to get messages from a new A, and think Alison is still alive. The girls see on the news that the body of a teenage girl—Tabitha Clark from New Jersey—was found floating in the water in Jamaica. The cops believe her death was an accident, but the Liars realize they killed an innocent girl.
Ruthless
Stress is getting to Spencer, and she starts to see hallucinations of Tabitha and her roommate Kelsey, whom she framed for drug possession to keep herself out of trouble. Spencer starts to believe Kelsey is A. Emily meets Kelsey at a party, and they immediately hit it off. But when Emily confides that Spencer framed her for drug possession, Kelsey overdoses and is sent to the Preserve for treatment. There, they learn that Tabitha was also a patient at the Preserve.
Stunning
When a woman named Gayle comes to Rosewood, the Liars begin to suspect that she might be A. But A murders Gayle, and then the girls discover Gayle was Tabitha's stepmother. At Gayle's funeral, Tabitha's father announces that his daughter's autopsy showed no traces of alcohol. This means that Tabitha was murdered, and he plans to reopen the investigation into her death.
Burned
As they begin to uncover clues, the Liars are led to believe that, this time, A is more than one person. Aria becomes friends with a boy named Graham, but then she realizes that he's Tabitha's ex-boyfriend. The girls begin to suspect Graham is working with Naomi under the cover of A. Just as they are planning to come clean about Tabitha's death, the four girls discover that they were not responsible for her murder—it was A who bludgeoned Tabitha to death.
Arc 4
Crushed
The Rosewood Day Prom is only a few weeks away, and the Liars are stressed. They're still trying to figure out who A could be. While Hanna, Spencer, and Emily become convinced that A is Aria's boyfriend, Noel, Aria doesn't want to believe it. Spencer meets Chase, who blogs about theories surrounding Alison DeLaurentis. He helps Spencer gather more information about Alison. At prom, Aria confronts Noel about Alison. Noel admits he loves Alison but does not know if she is still alive. The next day, Hanna gets a text from A telling her to go to the shed behind Rosewood Day. There, she finds Noel tied up. A texts the Liars and tells them they have failed to make progress.
Deadly
The Liars go to the police, trying to convince them that Alison is still alive. When they share the texts from A, the police dismiss the evidence, saying the texts all came from their own phones. Alison finally shows up again and attempts to kill the girls, telling them the police will believe they killed themselves because they missed her so much. It turns out that Alison was A with the help of Nick, her boyfriend. The police rescue the girls and catch Nick—but not Alison.
Toxic
High school is over, and it's summer again in Rosewood. But A is still out there. Even though the girls seem to be getting their lives together, the threat of A forever looms. Aria is getting famous for her paintings. Hanna is set to star in a movie about her life. Spencer has started an anti-bullying campaign. Emily is reconnecting with the girl who stole her heart. And then, right when they're starting to feel safe, A is back to bring all four of them down once and for all.
Vicious
Everyone believes the Liars are the ones who killed Alison, and they are awaiting their trial. Emily fakes her death so that she can secretly pursue Alison. The other girls, not knowing Emily's plan, spiral out of control in her absence. Just as their lives are falling apart, Alison reappears and is arrested. Finally, the Liars are free of A for good.
Pretty Little Liars Companion Novels
Pretty Little Secrets
Pretty Little Secrets takes us back to junior year, to a winter break no one ever heard about. What happens on winter break stays on winter break, right? Think again.
Ali's Pretty Little Lies
This is the prequel to Pretty Little Liars, set in the months leading up to Alison's disappearance.
Who stars in the Pretty Little Liars television adaptation?
Pretty Little Liars was adapted as a TV show, starring Troian Bellisario as Spencer Hastings, Lucy Hale as Aria Montgomery, Ashley Benson as Hanna Marin, Shay Mitchell as Emily Fields, Sasha Pieterse as Alison DiLaurentis, and Janel Parrish as Mona Vanderwaal. The series ran for a total of 160 episodes, starting in 2010 and ending in 2017. In 2019, a spin-off series called The Perfectionists, loosely based on Shephard's 2014 novel The Perfectionists, was released.
