Jason returns to town to stop Ali from getting too close to Mary. The girls learn something new about Mary and Mrs. DiLaurentis that leads them to a storm cellar full of clues. Ezra gets a call about someone in his past that could change his course. Noel Kahn grows more and more suspicious and rises to the top of the list of suspects for Uber A.

As romantic relationships move forward, the Liars investigate a new suspect in the murder case. With Ezra back in Rosewood, Aria must tell him the truth about her involvement with his book. Spencer and Caleb deal with a media leak that affects the campaign. Hanna takes a look at her life after an incident at work. Emily gets harassed by the stalker while she continues the search for Sara. Meanwhile, two lovers finally tie the knot with the help of a special officiant.

Mona returns to Rosewood in a very fragile state as she must answer to the police for faking her death. Matters only get worse when she is confronted by Lesli’s sister about Lesli’s inadvertent involvement in Mona’s plot. Hanna is determined to help Mona out, not only to reassure her she is safe from Alison but also to try and repair Mona’s friendship with Lesli. Emily tries to help Sara with her troubled home life by encouraging her to explore the possibility of emancipation. Spencer, on the other hand, finds help from someone from her past. Meanwhile, Alison grows closer to Lorenzo as she looks for support outside of her family.

With the Rosewood P.D. breathing down Hanna's neck about The Radley security footage, she opts to confess the truth to those closest to her in hopes they can help. Aria continues to search for answers, with help from Emily, on whether Ezra is as guilty as he seems. Spencer works together with Caleb to track down the new threat. Meanwhile, there is awkwardness all around when new love interests emerge and old ones resurface.

With the fallout of Hanna’s abduction still weighing heavily on the PLLs, the Liars begin to grow suspicious of Elliott Rollins as Ali’s condition worsens. Tensions rise between Liam, Aria and Ezra as they work on the book together. Spencer and Caleb are on edge, as neither of them want to talk about the awkward elephant in the room. Meanwhile, Emily receives a disturbing phone call and tries to find a way to see Ali.

The Rosewood P.D. begins to unravel the Liars’ cover-up, which leads them to question Rollins’ death altogether. Hanna deals with an inward battle on whether or not to tell the cops the truth, while Ezria struggles with an awkwardness in their relationship. Jenna reveals part of her plot and a new partner she is in cahoots with. Ali learns that the Liars gave her up as Charlotte’s killer in order to free Hanna, which does not go over well. Meanwhile, someone is murdered for playing with the wrong team.

Hanna is sure Jenna is to blame for a recent professional setback and is forced to bring Caleb up to speed on current events. Aria and Emily team up to investigate Sydney for more information about Jenna and her connection to A.D. Spencer grows closer to Detective Furey, while Aria struggles with her current situation with Ezra. Hanna’s turn at the game is more intense than she bargained for and leads to shocking consequences.

Convinced they know who A.D. is, the Liars gear up for a confrontation. Spencer, Hanna, and Caleb team up to investigate and discover new information about Charlotte’s death. Meanwhile, Mary Drake returns with a gift for Spencer and Alison.

With all signs pointing to Lesli as the tormentor in the hoodie, the PLLs are on a mission to get concrete proof before bringing their findings to the police. But as the girls ramp up their investigation, "A’s" threats escalate. Meanwhile, a friend of Emily’s makes her a surprising offer, and Spencer is pressured by her family to make an important decision.

Aria, Emily, Hanna and Spencer find themselves back in familiar territory with the Rosewood P.D. knocking at their doors looking for answers and their actions now affecting the loved ones around them. With her mother's job on the line, Hanna tries to come up with an alibi that could save all four of them with the help of her old high school friend, Lucas. Meanwhile, Emily comes clean about the last five years, and Aria goes the extra mile to keep Ezra's second book in play with her boss.

With the stalker threatening to kill all of them if they don’t divulge Charlotte’s killer by the election, the PLLs and company, at wit’s end, must boldly fight back. As Spencer and Toby work together to catch Sara Harvey, Yvonne wonders where Toby’s true affections lie. Ezra finishes the last chapter of his book, finally ready to say goodbye to Nicole; Aria comforts him during this emotional time and old feelings bubble to the surface. While Caleb works intently on his plan to protect Hanna, they reflect on what could have been. Meanwhile, Alison experiences strange visions and starts to question her sanity; Emily keeps tabs on her to make sure she’s okay.

One of the PLLs goes rogue to prove that Noel Kahn is Uber A, while the others try to find evidence to back her theory and worry about her emotional state. Emily unexpectedly turns to Paige for comfort in her time of need, which causes tension in her other relationships. Jason and Aria team up to look into Mary’s past and what she might be hiding.

After Spencer turns in desperation to Cece for help with her college application, she and Aria may find some answers at the Kahn brothers' party.

After lying to Alison and Jason about Charles, Kenneth comes clean about the family’s connection to the young boy. While he won’t give much detail about Charles’ past, he say’s enough to give the PLLs a clue of where to look for the missing pieces – Radley Sanitarium. With Radley now closed and the files shipped off to be shredded, the girls must act fast before all traces of Charles’ past disappear. Meanwhile, Caleb’s protective nature starts to pinch Hanna, and Spencer seeks a remedy for her sleeping issues.

Still reeling from the trauma of Hanna's abduction and dark fate, the Liars must shift their focus to another one of their own. In order to protect Alison from Uber A's threats, the PLLs snap into action at a chance to rescue her from the hospital. However, in doing so, they make a deadly mistake that changes everything.

Emily butts heads with teenager Addison, who appears to be a new version of high school Ali, and who may be connected to a familiar foe. Spencer confronts her mother about keeping family secrets. Aria confides in Holden about her relationship with Ezra, while Spencer turns to Detective Furey for help. And Jenna stirs up even more trouble when she returns to Rosewood with some insight into Noel Kahn and recent events.

There are mixed emotions in the DiLaurentis household when Charles declares he is coming home for his birthday. Mr. DiLaurentis wants to quickly get out of town to hide Ali and Jason from their brother, while Jason sees this as an opportunity to finally validate all of the early childhood memories he has of “Charlie.” The PLLs are just as split with Spencer and Hanna seeing this as the best chance they have to capture Charles, while Emily and Aria want to stay as far from him as possible. Will Jason be reunited with his brother, or is this just another of “A’s” traps? Meanwhile, Mona is shutting Mike out and Hanna gets an unwelcomed surprise.

After their latest run-in with Charles, tensions are at an all-time high with the PLLs and the town of Rosewood. Aria’s big moment of seeing her work displayed in an art gallery is in jeopardy as Ella is determined to keep her safe at home. Hanna is still uncomfortable with the unexpected scholarship money and is determined to give it back, even if that means ruining her chances at going to her school of choice. And to top it off, the one normal high-school rite of passage the girls are looking forward to is in danger as Rosewood High is considering not letting the PLLs attend prom due to security issues. Meanwhile, the more Alison learns about her brother the harder she finds it to connect a deranged murderer to the young blonde haired boy she sees in the photos and in her memories.

It is prom time at Rosewood High School, except for Alison, Aria, Emily, Hanna and Spencer who have been banned due to "security" concerns. As the girls see this as the final humiliating blow to their high school careers, the girls' mothers try to make the best of a bad situation by offering a home prom in Spencer's barn. At first reluctant, the PLLs agree and try to make the best out of a bad situation. But one to never miss a formal, Charles has other plans in store to make this a night they will never forget. Meanwhile, Veronica, Pam, Ashley and Ella use prom night to touch base on everything that has happened to their daughters.

Who killed Toby's mother? Who hit Alison in the head with the rock the night she went missing? Who is Red Coat? Who killed Bethany? Who is the Black Widow? Why has "A" been targeting the PLLs all this time? After years of torture, Alison, Aria, Emily, Hanna and Spencer finally come face-to-face with their tormentor and learn the story of how and why Charles became "A."

After Hanna’s shocking abduction by “Uber A,” the PLLs and company desperately race against the clock to save one of their own. The only way to do this is by handing over evidence of Charlotte’s real murderer to “Uber A.” In order to do so, the girls must decide what blatant lines they are willing to cross that they have never breached before; and once they cross that line, there is no turning back.

The girls’ lives have been turned upside down by their captivity and each one of them is looking for answers to make sense of their ordeal. Aria focuses on Andrew by trying to figure out who this boy really is while Emily tries to connect with a new friend. In true Spencer fashion, she is on a mission to get answers about Charles from Ali and Jason. Hanna wants to bring the four friends back together so they can move past what happened in the Dollhouse. Meanwhile, Alison is no longer the queen bee/mean girl she once was – but who is she now? A new friend tries to help her find the courage to start anew and find the “new” Alison.

While having to stay apart, Hanna turns match-maker, Spencer exploits her sister’s loss, Emily forges a letter, and Aria is upset in pottery.

As the girls are forced to stay in Rosewood, questions about the new mystery surface. A restless Aria starts to look suspicious as she heads back to Boston a little too quickly. But could Aria really be the one behind this? As Spencer, Emily and Hanna find themselves back in familiar territory, they aren't happy with going about solving this puzzle "the old way." Meanwhile, Emily continues to lie about her life in California and Alison keeps a close eye on her friends.

In order to prove Sara Harvey is behind the threats, Team Sparia reunites to find evidence of Sara's involvement before they go to the cops. Caleb puts together a plan with Hanna to fight back against the new stalker by using the security footage tapes. Meanwhile, Aria gets unexpected news from her family, and Ali comforts Emily in her time of need.