<P> During "Driving Miss Crazy", A.D. blackmails Aria into placing a burner phone with a pre-made audio recording to play over a sound system at the Hastings residence . The recording ends up being a secret conversation between Mary and Peter, which ultimately reveals that Peter and her sister were plotting to kill her . This leaves Peter in a rage, who begins to frantically search for Drake around the house, thinking that she might have planted the recording . He tears the speakers off the walls, instructing his wife and daughter not to listen to the "delusional ramblings" of a mentally unstable individual . After hearing the conversation playing on a loop, Veronica considers contacting the authorities but Spencer persuades her mother not to call the police . Later at night, Marco confronts Spencer outside her home, after learning that she is Caleb's ex-girlfriend . Furey further points out their romantic involvement gives Caleb enough motivation to protect her and cause a flood at The Radley that destroyed all of the hotel's security footage . Spencer threatens to embarrass Marco at the police station with personal details about their relationship, prompting him to drive off . After she gets in her car, Drake who was hiding in the backseat, covers Spencer's mouth and orders her to drive to the Lost Woods in order to explain her version of events . Mary denies planting the recorded conversation at the Hastings household, but isn't regretful Spencer heard it . After Spencer points out how Drake committed a heinous crime, Mary tells her not to judge . Through a flashback, we learn that Drake was told by Peter she would never see their daughter again . Peter and Jessica came up with a plan to use Peter's heart medication pills to kill her . Mary thwarted the plan and killed Jessica with his pills before burying the body at the Hastings' backyard . Feeling like she was cheated out of the chance to know Spencer, Drake asks her daughter to come live under the radar with her . Afterwards, Spencer goes home to confront her father . When she gets there, her parents are reading the letter Mary wrote to her . Peter, once again, tries to warn Spencer that Drake is manipulating her . Spencer alludes to her dad's involvement in the murder plot against Mary, but Peter makes no apologies for his actions . He clears up that his intention was to protect his family from a "deranged sociopath", and that he'd do so again if necessary . Peter storms out and Veronica informs Spencer that she is dropping out of the Senate due to fear of Peter's wrongdoings becoming public knowledge . Spencer meets up with Drake again, but this time it's to say goodbye . Mary assures Spencer she understands, and in return she implores her biological mother to forgive herself in order to move on with her life . As a reward for having obeyed Alex's orders, Aria is handed one piece of the puzzle and some confidential files . Furey reveals that he has crucial evidence that could lead him to Dunhill's killer, and Hanna worries . She then heads next to the Liar's Lament board game to play, and enlists Mona's help . Mona also teams up with Emily to find more information on Alison's terrible fertilization . They visit the doctor who performed the operation, not getting much information . Mona then heads to the address of the doctor's house, which she found in a magazine stolen from his office, and finds an envelope with money . She pressures the doctor, who reveals that he has never seen the giver and that everything was negotiated online . Hanna returns to where Archer was buried, in search of the shovels she and the others used to bury him . She then encounters a park ranger, who reveals the shovels were taken by the authorities . By the end of the episode, Mona returns home and it is revealed she took away the board game to investigate it . </P> <P> In "Choose Or Loose", Rosewood P.D. officers confiscate the Liars' personal stuff and cellphones through search warrants . Enraged, Spencer heads to the station to understand what's going on, and discovers that Detective Tanner is now handling the Dunhill case . Tanner expresses her concern about the possibility of the Liars being involved in the case, and indirectly threatens Spencer, saying that she always found them guilty of something, just did not know of what exactly . After her phone was taken, Aria discovers another one hidden inside an air duct that "A.D." left to communicate with her . Aria claims to meet "A.D." since she is a reliable person, and the tormentor sets a date, as long as Aria wears her uniform . In a room of The Radley, given by Hanna's mother, the Liars and Caleb get together to discuss the Dunhill's murder when the board game begins a new round: "Choose or Lose". The Liars have to choose one of them to go to jail accused of the murder or all of them go . Mona arrives shortly thereafter and warns the girls that Aria might be working with "A.D." The girls initially don't believe, but Mona exhibits evidence and a recording of Aria and "A.D.", leaving them in panic . Detective Tanner finds pieces of a windshield in the drain of Spencer's bathroom with traces of blood . Alex proceeds to impersonate Spencer again and visits Toby in his cabin, leading to a sexual encounter . </P> <P> During "Farewell, My Lovely", Caleb divulges to the Liars that Mona has the board game and they jump to the conclusion that she is Uber A. Spencer notices a message from Drake in a wine bottle while she was with the other Liars . Following its instructions, Spencer headed to the Lost Woods where she found Mary awaiting her . Preparing to leave town, Drake discloses to her daughter that she put the resort's deed in her name and Alison's so they could use it for money in case they needed legal assistance . Mary further states that preventing Lieutenant Tanner from obtaining arrest warrants for her family was the least she could do . Later that day, Hanna notices rose petals falling from the church's bell tower which prompts her to investigate . There she finds Mona dressed like she used to back when she was an outcast in high school . Hanna is puzzled over the fact that her friend keeps referring to her as Charlotte . Mona divulges she killed Charlotte and through flashbacks we see the two of them engaging in a heated confrontation . After realizing that her health condition hadn't improved after all and her intentions were to torture the Liars again through even worse approaches, Mona held a screwdriver to Charlotte's back . She taunted her former tormentor to jump or else she'd push her . Shortly after narrating a portion of the events, Mona suddenly grabs Hanna and attempts to throw her off the bell tower until Caleb and Spencer arrive just in time to prevent any collateral damage from happening . Mona is then taken to the Lost Woods and discloses to Spencer she messed up killing Charlotte . Asking what she meant by that, Spencer coaxed the full story from Vanderwaal who revealed that a fight broke out . Charlotte cruelly assures Mona the Liars will never love her back, causing Vanderwaal to gain the upper hand and shove her against a wall . A metal rod impales her spine, killing Charlotte instantly . Vanderwaal then threw her lifeless body from the bell tower and placed a rose on her hand before throwing rose petals . This revelation led to the final pieces of the puzzle being left for the Liars to find on Hanna's car . They placed the pieces into the board game, which A.D. had moved to the DiLaurentis residence . The phone from the game bid the Liars congratulations and through augmented reality informed them the grand prize was to discover Archer's corpse buried at Carol Ward's house . The girls rushed over there with shovels to dig the body up but Aria persuades her friends to stop playing the game and walk away . As they did, Tanner and the authorities turned up and the girls were all taken into custody . Fearing that they were about to be charged with first degree murder, the Liars are shocked to observe Drake in the interrogation room confessing to the murders of Dunhill and Jessica . While the Liars (minus Alison) knew she was accountable for her sister's homicide, they were shocked to witness Mary take the fall for Archer's involuntary vehicular manslaughter . Tanner allows the girls to walk away free but made it clear that she knew Drake wasn't responsible for Dunhill's death . Spencer tearfully watches Mary get taken away and whilst the two briefly make eye contact, Drake puts her finger to her lips, instructing Spencer not to stop her from sparing them a prison sentence . In the episode's closing sequence, Alex is seen driving off into the sunrise with the Liars' game pieces in a plastic bag . </P> <P> In "Till Death Do Us Part", a year has passed since A.D. went off the radar after obtaining closure in relation to Charlotte's murder . Mary, now an inmate, receives a visit from Alex, posing as Spencer, who asks for a favor . Later that night, the Liars and their respective partners are gathered at the Lost Woods for a joint bachelor / bachelorette party . An elusive figure in a black hoodie is watching them through the bushes while they're eating dinner . Suddenly, the anonymous entity turns around and is revealed to be Melissa . Melissa proceeds to spy on Aria talking over the phone to her doctor about her infertility issues . A few minutes later, she walks away from the resort to unzip the hoodie . As Melissa reaches into it, she pulls off a lifelike mask to reveal that it was actually Mona . Vanderwaal proceeds to FaceTime "A.D." and it is divulged that they sent her to the Lost Woods in the Melissa mask as a loyalty test . After successfully obeying her orders, Mona heads to Spencer's barn to knock her unconscious . Thereupon, Spencer wakes up in a cell and looks at what she believes to be a mirror . Alex, unable to keep up the ruse, quits impersonating a reflection . Spencer is visibly puzzled, and Alex startles her . She starts laughing gleefully as Drake walks up behind her and makes her way into Spencer's room, where she states they didn't think she'd wake up so early . Mary then injects Spencer with a sedative, causing her to fall asleep instantaneously . A few hours later, Spencer awakens once more, only this time attached to a holter monitor and with a foot chained to a bed . She comes face to face with Alex in tremendous stupefaction, who informs Spencer that their mother is preparing a special lunch for the three of them . Alex proceeds to share with Spencer details about the circumstances that lead to avenging their half - sister's memory . As a teenager, she obtained a job bartending at a pub in London where she met Wren, who originally mistook her for Spencer . Kingston disclosed to Alex her blood relations to Spencer, Charlotte, and Mary . The two eventually fell in love and began a romantic relationship . According to Alex, Melissa had been out of the picture at the time since she was dating a composer . It is ultimately revealed that the person whom Ezra ran into at the airport with Wren before almost leaving for Maine was Alex . The couple was engaging in a heated argument over whether or not Alex's true intentions were justice for Charlotte . Sometime afterwards, Kingston and Alex argued once more at his apartment in London, with Kingston advising Alex to come clean about her past to the Liars in hopes they'd embrace her . The pair kiss passionately before Alex picks up a gun and instructs Wren to shoot her in order to originate a matching wound to Spencer's . He initially hesitates but ends up doing so . Alex explains that the plan was to physically replace Spencer, but Kingston always thought of her as Alex . This prompted Alex to murder him out of anger, before turning his ashes into a diamond necklace . She then realizes the time and states that she has to get ready for Aria's wedding . A few hours later at Aria's dressing room, Pam walks in with one of Emily and Alison's daughters . Alex takes the baby into her arms and bounces her as she walks to a mirror . She starts chatting to the baby, complementing her looks and stating that she has her "daddy's eyes", revealing Wren as Alison's sperm donor and the biological father to her and Emily's children . Back at Alex's lair, Mary suddenly shows up to deliver Spencer's lunch and is met with accusations of having a helping hand in Alex's maneuvers . Mary reminds Spencer that she's a wanted convict for a murder she didn't commit and asks for her daughter's trust . This causes Spencer to ask where they are but Mary is unaware of the location, however, Drake mentions that Alex promised to keep both of them secure . Spencer interrogates Mary on why she never told her about Alex's existence, to which Drake declares being unsure whether Alex was alive or not until she paid her a visit a few weeks earlier . According to Mary, the existence of a second twin was unbeknownst to the Hastings, since Alex was born minutes after Spencer had already been handed over to Peter and Veronica . Mary, desperate to escape Radley, allowed Dr. Cochran to arrange Alex's adoption in exchange for $500,000 and a resignation from the psychiatric hospital . Alex was later adopted by a wealthy British couple . However, she started to develop mental health problems at an early age, and the family that fostered her refused to tarnish their reputation . Alex was then stripped off of her adoptive name and placed into an orphanage with her birth name . On her tenth birthday, Alex ran away from the Ambrose Home for Wayward Children, a year before Mary discovered she was there . Drake proceeds to unlock the code to Spencer's cell and the two share an emotional embrace . Spencer takes advantage of the momentum to steal one of Mary's hair pins to later pick the lock of her room . At the wedding, Ezra is revealed to be standing up Aria, and Alex watches as Aria addresses her father about what to do . She instructs Aria to try dialing her fiance again, however, Fitz fails to answer her calls . It is subsequently revealed that Alex kidnapped Ezra and is holding him prisoner in the same bunker Spencer's trapped at . The wedding is called off, after Aria discloses to her friends and father that she received a text from Fitz's phone stating he couldn't compromise to her . Later, Alison welcomes Aria to stay at the DiLaurentis household and informs that "Spencer" called to let them know she's bringing their friend something else to wear . Once Alex returns to her underground bunker, Ezra goes on to claim he and Spencer understand why she became A.D. and attempts to talk her out of her vengeful agenda . This angers Alex, who demands privacy, but not before reminding Fitz they met once . She recites the exact same words she spoke to him during their airport encounter with Wren, leaving Ezra stunned at her convincing portrayal of Spencer's voice . After Alex closes the doors to Fitz's cell, she turns to face Spencer, who insists that after learning about her sister's background, she empathizes with Alex and has forgiven her . She further persists that the other Liars will most likely forgive her, since they forgave Mona . Alex scoffs at this, aware that Vanderwaal was never truly welcomed by the Liars . Spencer puts two and together immediately and questions her sister if she developed feelings for Toby, considering they slept together twice . Alex notifies Spencer that whilst he settled for Yvonne, he was now widowed and free to be "with his one true love". Spencer declares that Alex can't keep her locked away forever, prompting her to happily assure that she can and that Spencer has their mother to thank for her safety . Alex reminds Spencer that Mary's protective nature is what kept her alive and that she rescued her from the abandoned school for blind students . This revelation causes Spencer to jump to the conclusion that Sydney was aiding Alex whilst Jenna and Noel chased the Liars . Alex giggles hysterically at her sister's assumption and clarifies that Driscoll was merely a "one - off" deal . As it turns out, Alex blackmailed Sydney after randomly discovering that she was stealing from the bank she works . Driscoll agreed to persuade Aria into joining the A-Team . She then explains that Jenna requested Noel to search for her whereabouts . Marshall was aware Charlotte had another sister and that she left Alex her possessions . Although Jenna didn't know Alex's name nor her physical attributes, she offered to do her bidding in exchange for one last chance to regain her eye sight . Alex paid for Jenna's treatments, which proved unsuccessful, therefore becoming counterproductive to her agenda . As for Sara, Charlotte told her she hid "her greatest treasure" at The Radley . Harvey deduced it was money, when it was actually Mary's medical file that Spencer and Toby found in the underground alley beneath Sara's hotel room . Alex further clarifies that all Charlotte asked for was a family . Alex was introduced to her half - sister prior to her death, when the latter flew from a transatlantic flight to France just to meet her . In a flashback at an airport, Charlotte is seen talking to Wren over the phone about Alex. She says that she found twelve Alex Drake's and none were related to her . After Wren informs Charlotte that Alex looks a lot like someone they're acquainted with, she is stunned to stumble upon a girl identical to Spencer before realizing it's her twin sister . According to Alex, the two bonded instantaneously and walked the streets of Paris until the sun came up, feeling like they'd known each other their whole lives . She goes on to clarify that Charlotte met Archer on the plane, and they initiated a romantic relationship . Spencer questions if Archer was on the A-Team as well, but Alex quickly dismisses her doubts by explaining that his severe mistreatments towards Alison at Welby was a stunt he pulled on his own . He persuaded Mary into aiding him, believing that her niece was the mastermind who orchestrated Charlotte's murder . Wren and Alex went on several double dates with Charlotte and Archer before she returned to Rosewood to continue the "A" game . During another flashback at a bar, Alex attempts to convince Charlotte to stay with her in London, thinking she allowed the Liars to have power over her, Charlotte however believed herself to be the one with the power . After she suggests departing with Charlotte to meet Spencer, she warns Alex to stay away from the Hastings as far as possible . Alex insinuates that Charlotte wanted Spencer all to herself, prompting her to disprove Alex's hints of jealousy . She insists on offering Charlotte a ride to the airport, but Charlotte declines, further justifying that a pre-meditated goodbye would be too hard to handle . The sisters share a final embrace and Charlotte gives Alex a vinyl record of Patsy Cline's Greatest Hits record as a goodbye gift . Back in present time, Alex explains that Charlotte never returned to London, and the next time she saw her was when she first paid a visit to her grave . Spencer asks Alex why she believed Charlotte's depiction of her . Alex responds that whilst their interactions were brief, Charlotte seemed honest enough when she described Spencer as "toxic". She then states that she has to leave again, and opens up the door to Ezra's room before leaving . She is later seen at the barn walking up to her sister's rescue horse, Bashful, and tries to put a saddle on him . The horse rears, recognizing that Alex isn't Spencer . Toby runs into the pen and settles the horse and asks if she's okay . Alex responds that she is, and the best thing to do when the horse gets like this is to walk away . She then leaves, and Toby looks at her confused, as this contradicted what Spencer had said to him the day before . A few hours later, Alex is seated on a bench outside of the * Hastings and Hastings * law firm . Jenna emerges from the building with Veronica, and the two women briefly discuss a legal situation involving Addison's behavior at school . After Veronica leaves, Marshall sniffs the air around Alex and questions "Spencer" on whether she's sporting a new perfume . Alex laughs it off, explaining that she spent the morning taking care of Spencer's rescue horse, before heading in the opposite direction . After she walks away, Jenna pulls out her phone and calls Toby to warn him that there's an impostor posing as his ex-girlfriend . Aria is about to send an S.O.S. to Spencer when Toby walks into the DiLaurentis household and orders her not to do it . He then unveils to the Liars and Caleb that he knows about the existence of Spencer's twin sister, as the book that Alex gave him didn't have notes in it, and Spencer was always writing notes in it . He goes on to speculate that twins run in the family that it's time for Plan B and that Alex needs to tell her who she is . Alex is then spotted angrily leaving a house with Drake in tow . Mary points out that Alex promised she wouldn't injure Spencer, and she angrily proclaims her need to dispose of "the proof" before grabbing an ax off the side of the building . Drake states that if they leave straightaway, they can arrange a mother - daughter trip to Europe . Alex insists that she's not going anywhere without Toby and claims he's in love with her . Mary responds that Toby's in love with Spencer, which causes Alex to furiously yell that she already became her sister . Mary notifies Alex that she knows what it feels like to believe in something so desperately that you start to believe it's true . Alex wisecracks that she can't fathom her mother's words and punches Drake in the nose, knocking her out . In the meantime, Mona arrives at the DiLaurentis household and explains to the Liars that the elusive figure in a black hoodie who paid her a visit at Welby a year earlier was Wren, hellbent on killing her under Alex's orders . However, Vanderwaal persuaded him and Alex into sparing her life by helping Mary escape prison . Through Mona's assistance, the Liars, Toby and Caleb discover where Alex is after Vanderwaal divulges the coordinates of their enemy's lair . They quickly figure it out that Alex bought the house Toby built and must be holding Spencer captive there . They then rush out to find them . In the meantime, Alex is seen stalking through the hallways of the bunker clutching the ax . She heads to Spencer's room, only to discover that both her sister and Ezra have escaped . She is annoyed by this and puts the ax on her shoulder before walking off to find them . Spencer and Fitz discover that what they believed was a house and lawn is in fact a fake scenario Alex built underground . At the same time, the Liars, Caleb, and Toby arrive at Toby's former house to discover that the living room is filled with replicas of Spencer's furniture . On that occasion, they find the pathway to where Spencer, Ezra, and Alex are . Ezra informs Spencer that the only way out is to go back, but Spencer refuses to go through the bunker again . Moments later, Alex switches the lights out and sneaks up behind Spencer and Fitz and attempts to murder them . She knocks Ezra down and his head hits on a rock . Alex rises her ax to murder him, but Spencer jumps in front of Fitz and orders Alex to stop . Alex mockingly mimics every word Spencer utters, until Spencer states that it's not too late to be family . This irritates Alex, who claims that it is before raising the ax and striking down . Spencer bulldozes Alex and knocks her to the ground, leading them to roll around, punching and hitting each other . Finally, they break apart and one twin goes for the ax, grabbing it, and the other twin grabs it and they struggle for it . However, the Liars, Caleb and Toby burst in, with Cavanaugh holding his gun up and ordering both twins to drop it and both do so instantaneously . Alex tries to convince Toby that's she's Spencer and Spencer quickly warns him not to listen to her . Alex gazes at Spencer astonished and accuses her of being deranged . Toby puts his gun away and walks up to Alex looking her in the eyes before pinning her hands behind her . He asks her to tell him her favorite quote from the book she gave him, and Alex can't answer the question . However, Spencer quotes the line in fluent French, leaving Alex furiously stunned . A police officer runs in and Mona discloses to the Liars that she contacted the authorities . The officer states that Mary was caught a few blocks away, and handcuffs Alex . Whilst the man takes her away from Toby, Alex pauses in front of Vanderwaal and heatedly states "no one can call you Loser Mona anymore ." Mona enthusiastically replies "you don't know the half of it ." A defeated Alex is taken into custody upon their interaction . At an unknown time, Vanderwaal is seen running a doll store in France . Once she finishes selling an item to a customer, the officer who arrested Alex and Mary walks inside to greet Mona with a kiss, revealing that they were somehow in cahoots . They make ensuing dinner plans and after he exits the shop, Vanderwaal heads to a basement . A dollhouse is set up with two dolls seated in the upper division, to which Mona voices that it's tea - time before handing them a toy teapot . Behind the dollhouse, a light goes on in a room that shows Alex and Mary, who are costumed as dolls while sipping tea together . Alex unleashes a heavy sigh, and Mary professes to her daughter that Vanderwaal can't hold them hostage indefinitely . Alex, embracing the unavoidable, rolls her eyes and elucidates, "Of course she can, she's Mona". She then irritably glares through the glass at Vanderwaal, who is also sipping tea and looking utterly satisfied, knowing she has finally taken control of the "A" game again and owns two dolls of her own . </P>

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