Mona Vanderwaal

Mona Vanderwall was a student at Rosewood High School. She is a former nerd who used to idolize Alison DiLaurentis in the shadows. She transformed herself to Rosewood's "It Girl/Queen Bee" along with one of Alison's former friend, Hanna Marin. It's later revealed Mona is "A", or at least part of the group. Mona's unique eye color is often noticed when she is "A ".

Biography
Deep down, Mona will never forget the way Alison treated her, but being popular, there was no time to be sentimental about things from the past. Ironically, Mona begins behaving like Alison after she resumes Alison's place as a Queen Bee. She taunts Lucas and calls him a hermaphrodite, Alison-style.

Mona shoplifts for fun. She has never been caught due to the fact that she has become so good at it. She and Hanna became best friends when Alison's crowd gets disbanded. Mona figures that Hanna would not give up the chance to become popular. Their friendship stays strong until the ever so infamous "A" begins torturing the girls, forcing Hanna to become closer to her old friends. The other Pretty Little Liars, besides Hanna, don't care much for Mona, and this is a source of conflict in certain episodes. She can also speak French, hack computers, and do voice impressions.

Mona is revealed to be "A" in the season 2 finale. She considers herself a genius, but also has a personality disorder (according to Dr. Sullivan) and is now in the Radley Sanitarium. Mona is possibly under the influence of someone in a red coat whose identity is still unknown.

Season 1
In one of Aria's flashbacks, early in the series, Mona is shown with glasses and pigtails, trying to hang out with Alison and Aria. She asks them to wait up, but Alison tells Aria to ignore her, and cruelly, Aria obeys, running away from dorky Mona. Mona is crushed and wraps her arms around herself to warm up.

In the episode "Keep Your Friends Close," Mona is throwing a birthday party for herself, which she calls "Camp Mona" and gives select invites to her friends, including Hanna and the rest of the liars, as they are her BFFs friends. The rest of the Liars aren't interested, though Hanna tries to persuade them to come and that Mona has redeeming qualities, but they do not change their minds. This changes, though, when "A" tells the Liars that information will be revealed at Mona's birthday party.

Then, Mona hears a rumor (thanks to a text from "A") that Hanna lost weight thanks to liposuction. Mona breaks off their friendship due to anger, going as far as to dis-invite Hanna from her birthday party. She also dis-invites her because Hanna refused to ditch school with Mona, despite Hanna's mother giving Hanna plenty of cash to spend on Mona. So, ironically, Spencer, Aria, and Emily attend Camp Mona without Hanna. Camp Mona turns out to be an over-the-top bash, complete with massage deck, food tents, makeshift hair parlor, and matching T-shirts for all attendees. Her gift table is piled high with presents.

In the next episode, when Hanna is hospitalized due to her run in with "A" at the end of the party, Mona visits her in the hospital and apologized, realizing that she was mad at Hanna for a stupid reason. Hanna gladly accepts her apology and they become BFF's once again. While visiting Hanna, Mona told Hanna the reason she chose her to be her best friend. At a party, chubby Hanna vomited while on the trampoline. When she realized everyone was laughing at her she bowed, no longer affected by peoples remarks. Mona found that to be a life lesson. Mona believed that if Hanna could get over people teasing and ignore it, so could she.

Mona throws a surprise "Welcome Back!" party when she was released from the hospital. Mona and Hanna are still BFFs but not like before. Their friendship isn't as strong, due to the fact that Hanna's relationships with her former BFFs, are growing once again.

Mona is not seen in a few episodes until she appears in "The Badass Seed," gossiping with Hanna about her morning shower with Caleb. Mona is in the school play with the rest of the Liars; she witnesses Aria call Mr. Fitz "Ezra."

In "Monsters in the End," she destroys a letter from Caleb, expressing his love for Hanna, due to the feeling need to protect Hanna from being hurt again. Hanna does not find about this until later and thinks even more badly of Caleb as a result.

Season 2
In "It's Alive," when Hanna finds out from Caleb that Mona never forwarded Caleb's goodbye letter to her, but instead lied, leading her on to believe Caleb was worse than he actually was, she is distressed and angry with Mona.

Noel Kahn returns to school in the same episode, and Mona begins dating him, to Hanna's surprise. Hanna is angry with her friend for lying to her, but agrees not to judge her for dating Noel. Eventually, Hanna confronts Mona later in the episode, just before her date with Noel. When Hanna leaves, Noel detects something wrong, and Mona just sulks.

In the next episode, when the Pretty Little Liars' parents have placed a ban on them hanging out together, the girls sit at different lunch tables. Mona tries to invite Hanna to sit with her, but Hanna is still too sore at her to be her friend again, so all five girls sit at separate lunch tables, eating alone.

Hanna and Mona eventually rekindle their friendship; Mona calls it spiritual. They agree to keep their romantic lives (i.e. Caleb and Noel) out of discussion for the time being, while their friendship repairs, in order to avoid more arguments. However, Hanna does find out why Mona is dating Noel: "He has bad-boy cred now too." (Because of his suspension)

Later in "Never Letting Go," Mona takes over as the boss of the fashion show. Spencer expresses an intense dislike for Mona's attitude. Despite her bossiness and aggression she is able to have the show run smoothly until "A" sabotages the CD. In an open display of favoritism, Mona appoints Noel as fashion show DJ.

In "Touched by an 'A'-ngel," Mona accompanies Hanna in blowing off school to try on her bridesmaid dress for Isabel's wedding. Before meeting her, Mona had formed a negative opinion of Kate, based on what she considered a hideously ugly gown. However, when she meets Kate, she immediately takes a liking to her style. When Kate invites Mona and Hanna to lunch, Mona accepts, while Hanna declines, frustrating Hanna. She accompanies Hanna on a trip to a horse farm, due to Mona's pretending she went to equestrian camp in order to fit in with Kate and her friends. At the farm, they meet Kate's friends. Hanna displays her ignorance about certain cultural references that Kate and her friends make, so Mona cuts in, laughing off Hanna's remarks, trying to save her friend’s face. Later Mona and Hanna are walking through some random woods, their faces stained with dirt. The girls had managed to lose Kate's horses. Hanna gets Mona to admit that equestrian camp had never happened. Hanna snaps at Mona, accusing her of befriending Kate for selfish reasons, and Mona counters that Hanna has been bad tempered ever since Caleb left. Hanna later apologizes.

After returning to the stable, Hanna expresses to Mona her feelings that Kate and her friends were nasty towards her and also considered Hanna clueless. Mona suggests that Hanna wasn't trying hard enough, making Hanna really rail against her future step family and Kate's friends, writing them all off to hell. It turns out that Kate and her friends outside the stable could overhear the whole exchange after Hanna accidentally set her riding helmet on the loudspeaker switch. The girls rush out to undo the damage, but Kate walks away miffed, with her friends at her heels. Mona does seem sincerely apologetic about her mistake and the fallout Hanna has with Kate and her friends.

Later in "I Must Confess," Mona is seen during Dr. Sullivan's assembly on cyber-bullying and rolls her eyes at Hanna, mouthing the word "boring."

In the prequel episode, "The First Secret," Mona is insulted by Alison after trying unsuccessfully to sit with her and the other girls in the school cafeteria. Rebuffed, Mona goes next to Lucas' table.

The familiar scene where Mona spots Aria and Alison eating their frozen yogurt as they walk is replayed. Mona calls out to join them, and Aria looks inclined to stop, but Alison propels Aria forward in an attempt to lose Mona. It is now revealed that this event took place on the eve of Halloween 2008. Mona turns around, rejected, chilled, and upset.

Later on in the school hallways, Lucas bumps into Alison, dumping his drink on her. Angry, Alison rejects Lucas' apologies, mercilessly calling him "Hermie" and publicly suggesting that he's really a hermaphrodite. When Alison walks away, Lucas growls that she will get what's coming to her, and Mona nods uncomfortably in silent agreement, having witnessed the whole exchange. How Mona ever took to calling Lucas by that same insult is a mystery.

At Noel's halloween bash, Mona is dressed as cat woman. Alison doesn't seem to recognize her (though for Mona that's probably a good thing) when Mona approaches Alison and with a warm hello. When Alison asks if she knows her, Mona mysteriously responds no, but Alison will. When Jenna saunters away from her own exchange with Alison, Mona declares her the best Gaga, and the two introduce themselves, seeming to start a friendship.

When Hanna plans a surprise birthday party for Caleb in "A Hot Piece of A, she does not invite Mona, thinking her still against Caleb. However, she invites herself and Noel, claiming they're friends now. Hanna agrees, and the couple saunters away together in the Rosewood High hallways.

At the party, Mona and Noel question Hanna's decision to order 12 pizzas with green peppers as Noel is allergic. After the boat fiasco, Mona is seen with Noel outside, dripping wet, after they "took a dip" in the lake.

The next day in school in "Let the Water Hold Me Down," Mona expresses her worry to Hanna that she is losing Noel. Apparently, he spent most of the previous night on the phone, and she had to convince him to go skinny dipping just to get his attention. As Mona walks with Hanna in the school hallways, they see a student taking down Hanna's homecoming picture; Mona barks at him in her friend's defense. When she continues speaking, Hanna is completely innatentive (thinking about Lucas being missing). Mona is hurt by her friend's insensitivity, and Hanna rushes to a bathroom stall, leaving her pal behind.

Later in the episode, Spencer sees Mona getting off the train in Rosewood. Apparently both had spent the evening in Philadelphia. Mona tells Spencer that Noel broke up with her, looking heart-broken. She had been on a shopping spree as therapy for her distress. She offers Spencer some of the cashmere sweaters she had bought. Spencer declines and comforts Mona with empowering words, telling her she's better than Noel. Mona thanks her and gives Spencer a rare compliment.

In "The Blond Leading the Blind," Hanna tries to console Mona over her break-up with Noel, but Mona is still upset with Hanna. Mona grabs a necklace out of her locker and tries to return it to Noel, who is standing nearby. He promptly dumps it in the trash and laughs when Mona begins to cry. Hanna follows a tearful Mona into the bathroom and tries to comfort her, though she can't seem to find the right words. They agree to use their fake IDs at Rive Gauche later that night. But, when they get there, Hanna and Mona spot Jenna and Noel sitting together in Rive Gauche.

In "The Naked Truth," Mona is her usual impertinent self during the school "Truth Up Day" Program. Ashley runs Mona's and Emily's focus group, and Mona mocks and gives attitude, even to her best friend's mom.

Then, Emily is intimidated and told off by Tamborelli. Mona looks on, and Emily notices her staring. She decides to approach Mona about it. She apologizes to Mona for letting Alison torture her all those years. Even though Mona puts on her nonchalant exterior, she seems genuinely effected by the apology. She sides with Emily and lets her know Tamborelli isn't so lily-white himself.

She goes out of her way to help Emily get back on the swim team by blackmailing the school vice principal. She adeptly hacks into his computer though "he changed the password" and digs up compromising information. She confronts Tamborelli herself, securing Emily's place back on the team. When Emily thanks her, Mona responds "that's what friends are for." She goes on to discuss with Emily what she should wear to go to a swim meet because she would like to come and see her. This seems to show that Mona has a very forgiving personality and only puts on a popular, not caring face as a front to protect herself. At the same time, Hanna is going through her own ordeal, being accused of sending racy pictures of Kate. Mona stands by her as well.

In "Breaking The Code," Mona tells Hanna about going to the mall, which Hanna forgets, but promises that they will hang out the next day at Hannah's house. When Mona receives a text from someone, Hanna asks who it is from and Mona lies. After Hanna leaves, it is revealed that the text is from none other than "A." While hanging out in Hanna's bedroom to pick out clothes as promised, Hanna is again inattentive to her friend, paying more attention to her phone, until Mona receives another message from A and tells Hanna about it. She says that it had been happening for a few days and that the messages have been accusing her of shoplifting things. Hanna asks if any of the texts are about her, and Mona replies that there are more about Hanna's mom. She shows her a suggestive photo of Ashley and Officer Wilden. Hanna lies and says it's obviously photoshopped, to which Mona agrees. When Hanna questions what Mona would do with the picture if the mystery texter started threatening her, Mona replies that if she can live through Alison, she can survive this anonymous texting.

Later, Mona visits Hanna's house again and shows Hanna an incident report from when Hanna shoplifted the sunglasses. The report was put into Mona's mailbox by A. A had ordered Mona to give the incident report and the picture to the Rosewood Observer or else she'd be filling out a police report herself. Hanna tells Mona about A and that the threat isn't a joke. When Mona asks about what A did, Hanna does not reply properly. When Mona wants to know what to do about the report, Hanna isn't sure but promises she will think of something in time. Mona asks her to hurry, showing the text she got from A which says that she only had until 10 am the next day.

The next day, at 10.15 AM, Hanna, believing that Mona turned her mom in, goes to tell Mona that she doesn't blame her. Mona reveals that she went to the jewelry store and returned the necklace she stole. The store owners called the police and it ended with Mona's mom working it out so Mona would just be serving food to the homeless. Hanna thanks her and Mona replies that she wouldn't do anything that would hurt her best friend and her mom.

At school, when Hanna passes by Mona's table, she shows Hanna another A message on an apple. Freaked out about it, she decides to take the rest of the day off because she doesn't want to be a sitting target. However Hanna invites Mona to sit with her, Aria,and Emily. Mona was reluctant first, feeling that they won't accept her, but eventually agrees sit together with them.

In UnmAsked, Mona attends the Rosewood Masquerade Ball with the other girls and later goes with Spencer to the Lost Woods hotel, after Spencer deduces that A had rented the room next to the one Alison was staying in. In the room, they find sketches of a Black Swan costume and conclude that A must be wearing it at the ball. Mona offers Spencer a stick of gum, but Spencer turns her down. While going through A's belongings, Spencer locates a gum wrapper from the same brand of gum Mona just offered her. He tells Mona that he changed his mind and that he'd like a stick of gum after all. Mona agrees, but says she doesn't have any more on her, but that she can go get some out of her car while she goes to call Hanna. She leaves the hotel room while Spencer continues to search. A few minutes later, Mona returns to the room and angrily says "I found the gum!" Spencer looks up from the book and says "You didn't call Hanna...because you're A." Spencer turns around and we see Mona wearing a black hoodie. Mona admits she's A and congratulates Spencer on figuring it out, right before knocking her out.

Spencer wakes up in a car with Mona driving recklessly towards Lookout Point. Mona says that she wants Spencer to join the A-team. Spencer asks if the reason Mona became A was her anger at them for letting Alison bully her. Mona laughs and says that she got over that a long time ago. Mona reveals that she became A because she hated them for stealing Hanna's friendship from her. Spencer pleads with Mona to stop, encouraging her that Hanna is still her friend. As they drive, Spencer is secretly recording their conversation on her phone and sending the video to Aria's phone. Aria, Hanna, and Emily leave the ball immediately and drive to Lookout Point. When they show up, Spencer and Mona struggle, resulting in Mona falling off the edge. Spencer reaches out, trying to save her, but fails.

As the police and medical personnel arrive on the scene, Mona is revealed to have survived the fall. Dr. Sullivan makes her return to Rosewood and diagnoses Mona with a personality disorder that caused her to experience a sense of hyper-reality and omnipresence. Mona is found criminally insane and sent to an asylum for treatment. Dr. Sullivan is confident that Mona can be helped with treatment.

During the final few scenes of the episode, Mona says in a voice-over that everything has gone according to plan and that now the girls will feel safe and unlock their doors at night, even though there's still a threat against them. While in the asylum, she receives a visit from someone in a red coat. She looks up at this person, smiles, and says that she did everything they told her to do.

Season 3
In It Happened 'That Night', we find Hanna has been visiting Mona in the Radley Sanitarium, and that Wren Kingston is working as one of her doctors. Hanna wants answers; she wants to know what she did to make Mona hate her so much. Each time Mona just sits their still and almost lifeless. She has a glazed look in her eyes and remains with a stoic expression. After Hanna leaves, Mona spies as Wren and Hanna speak about her.

Later when Wren calls Hanna he states that Mona is making progress and he thinks because it's from Hanna's visits. At the end of the episode Hanna tries to get through to Mona again, and askes her if she wants her to keep coming back. Mona looks over and smiles. Hanna thinks that she is smiling at her, but

then realizes she is smiling at an empty chair. Mona is actually hallucinating and sees Alison holding her "Lolita" book, wearing a red coat, smiling back.

In Blood Is The New Black, Mona is still being visited by hanna and also Mona speaks for the first time in the season. Her first words are "Your getting them again aren't you? The texts."

Trivia

 * Janel Parrish originally auditioned for the role of Spencer Hastings. After being informed she was not going to receive the part, she re-auditioned for the role of Mona, and received the part.
 * In "Never Letting Go," Mona mocks Aria at the fashion show dress rehearsal while Aria is practicing her catwalk: "Are your legs always that short, Aria?" In the same episode, Spencer alludes to Mona being five feet tall. Mona's and Aria's wikia page both show that they share the same exact height: 5"2!
 * Mona along with Hanna have appeared in character in commercials for TRESemme hair products. Including TRESemme climate control and TRESemme Fresh start.
 * Mona is up on her Wizard of Oz references, as she tells Lucas in "The Perfect Storm " to ask the wizard to make him a man. "A" is up on their Wizard of Oz references too, custom designing a fortune cookie that reads "There's No Place Like Homecoming." (Dorothy's words at the end of the film: There's No Place Like Home.") Also, in "Can You Hear Me Now?," "A" sends a flier towards the Pretty Little Liars that reads, "Ding Dong, the Bitch is Dead," a reprisal of the film's song "Ding Dong, the Witch is Dead."
 * Janel Parrish revealed in an interview that she did not know she was "A" until a week before they started filming for the finale, but she was always hoping that she was "A." Janel suspected a lot of people were "A" but she was most suspicious of Jenna. She also mentioned that in the next season, Mona will explain how she did things and get another visit from the "mysterious stranger."