<p>In this theory, Jenna has a big secret and knows about A.D too. Both of them are evil here ! (warning, it's very long)
</p><p>First of all, three importants facts:
</p><p>During the last 5 years, Toby found out Charlotte lied about Marion's death.
</p><p>Mary killed Marion. Charlotte protected Mary, but also wanted to be part of Jessica's family. She cared for both of the twins.
</p><p>Charlotte lied in 6x10. But flashbacks are shown in the perspective of people who told them, and for Charlotte these memories were true as she was deeply attached to Jessica and her children ! (more of this right after)
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</p><p>Bethany = Charlotte, not because of a split personality case, just a fake name (it's maybe far fetched, but sometimes simples solutions are the best). Bethany's roomate Leslie (who obviously never met a girl named Charlotte) heard the name Charles for the first time the night of Ali's disappearance. What if, after transioning, Charles was called Charlotte only by Mrs D, while the other people at Radley knew her as Bethany Young. Charles was dead. Maybe they wanted an all new identity for her, and in some way changing her name to Charlotte wasn't enough. In Rosewood, Charlotte was Cece, in Radley, she was Bethany. After the night when a girl was buried alive, why no one signaled Bethany's disappearance from Radley ? Well, we learned that after this night Charlotte stayed in Radley thanks to Jessica and Detective Wilden; so if CC = Beth, there was no reason to signal her, and she probably stayed in isolation so Leslie never saw her again til she was released.
</p><p>Both Mary and Charlotte were in Radley; Charlotte was the smartest, I believe she found out early about Mary Drake existence, Jessica's twin; and also knew, no matter what, that Mrs D was the one present in her life, the one who cared. Charlotte asked Jessica about it, so she confessed. From that moment, Mrs D would be only an aunt for Charlotte... (who else in Radley could call Jessica "aunt Jessie"? maybe a certain Bethany Young. Strange coïncidence, don't you think ?!). Charlotte knew the truth, but Jessica, Jason and Alison were still the ones she considered as her true family, so she freaked out when Mrs D told her now they only gonna be aunt and niece ! That's how she developed obsession toward all the DiLaurentis. An envy to be as close as possible to Jason and Ali. Marion Cavanaugh was perhaps the one who helped Mary to contact her daughter, but things went wrong, deadly. Maybe Mary was afraid of people who knew about Charlotte.
</p><p>(Now the important part, AD and the killer chapters !) The name "Bethany Young" doesn't come from nowhere. Jessica cared for "her niece", she told her every knowledge she had on her twin. Mary had another son, Charlotte's brother. A boy separated from Charlotte by Jessica's lies (kind of), just like in Bethany's drawings. He was adopted by a family in another city, the Young. Both Jessica and Charlotte agreed about naming her with her brother's family name. But they never met, the Young never heard about Bethany, that's why we never saw them. But still we can imagine that the cops were in contact with them during the investigation, weren't they ? Well, with their legendary efficiency, it's easy for me to believe that someone tricked them, posing as Mr Young for example.
</p><p>And who I think is the one who did it ? Charlotte's dad a.k.a. Peter Hastings. Peter knew Mary was the twin he slept with. He knew about her pregnancy and probably helped for the DiLaurentis' adoption of Charles (Jason is not Peter's, Charles was). Cheating was already huge, Veronica would have never accept a child from a crazy twin. Peter had to bury that secret...
</p><p>A.D a.k.a. the Young's child a.k.a. someone we know with a different name in Rosewood a.k.a. Uber A was working with Mrs D, to be able to had news about Charlotte. I'm calling it, he's Jessica's killer. The one she couldn't protect anymore. The last Mrs D's secret, even Charlotte didn't know Jessica met A.D and told him the truth about her and Mary. When Jessica found that Alison was alive, she took a decision: No more secrets ! She wanted to reveal everything, introduced Charlotte, brought back Mary into their lives, exposing Peter (that's why he was so eager to ask her about their agreement), and exposing A.D existence by blowing his life. Back then, he wasn't ready to fully assume a sister and a mother who were in a mental institute. It was too much, too fast; he had to silence Jessica. A.D is Lucas. Mrs D made him a fake background life in Rosewood. The Young believed their son was in some private school.
</p><p>The Dollhouse was built by Elliott and Mary, way before Charlotte thought about abducting the Liars there. A place where Mary could met Charlotte, thanks to Elliott, her doctor, who was able to secretly get Charlotte out of Radley. Elliott is Sara's kidnapper too. He took that blonde girl who had runaway from her home because of her resemblance with Ali. And it worked, Sara's presence in the future Dollhouse calmed down Charlotte after the event of that night. Sara and Charlotte developed a forced sister bond. Elliott was Varjak and it was his idea to use Sara as a Red Coat decoy.
</p><p>In 6B, after Charlotte's release, Lucas was ready to kill her. He wanted to confront her the night of her death. They met quickly at the church, then he had second thoughts; that's when somebody else (another person who had a grudge against Charlotte) came here and roughly killed Charlotte. Lucas came back to make peace with his sister but found her dead. In despair, he staged her death in a way that could incriminate the Hastings (A.D knows about Charlotte's father and hates him). The biggest twist is that the killer witnessed Lucas and Charlotte's reunion cause the killer acted in A.D's back. The killer then knows about the Charlotte's brother existence and his will to keep this status a secret. With secrets messages/threats he/she blackmailed Lucas into exposing him if he try to get revenge, that is how Lucas became A.D, that's why he found and worked with Mary and Elliott, and started blackmailing the Liars. He is tied by the killer. Lucas truly wants the killer to be found by the girls.
</p><p>Charlotte's killer is Jenna ! She is the puppetmaster behind the mess that started in 6B. She killed Charlotte because... revenge, remember Charlotte tried to kill Jenna in the first place. It was pure and evil payback ! And Toby covered for her. He told her about Marion's murder. Jenna is twisted enough to claim she killed Charlotte only for Toby. Amoji/A.D acted like a child or like someone who aren't totally free of his actions (lame messages/threats, lame emojis, lame actions like not being able to stop Caleb to hack his computer).
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</p><p>My theory is that Jenna will come back in 7A, but we will not found more information about the killer until 7B. For most of the season, A.D will appear as the only bad one, and Jenna as a normal Rosewood citizen. Who would suspect a "blind bitch" who seemed to have "<i>made peace</i>" with the Liars ? Jenna is a smart girl, she always had people to do her dirty work (Garrett, Shana, Nigel...) but she probably can do worst on her own.
</p><p>I can see 7x20's revelations being the ultimate confrontation between Jenna and Alison, with both telling what they've been through because of each other since the First Secret; while elsewhere the Liars, with Mona's help, will confront Lucas !!!
</p><p>Lucas is one Big Bad, he killed Jessica, and could kill again to protect his secrets. But, <i>all</i> of this is also <i>connected</i> to Jenna.
</p><p><i>Noel's secret</i>: if Jenna and Noel come back in the show, I believe they will try to tie all the lose ends. Noel was scared of what Alison could reveal about him. It must have been a "life or death" situation/ level of importance. Noel dated Jenna. Was it really love ? Or out of guilt perhaps ??? How ashamed would Noel be if the secret concerned his ex-girlfriend's blindness !? Maybe he's the one behind the "Jenna Thing" as the person who gave the firecracker to Alison.
</p><p><i>Melissa</i>: she was a manipulative, crazy, mean woman while she was "protecting Spencer". Could Jenna be spiteful enough to get revenge from her by blackmailing Melissa about the confession's tape, and in the same time get money with this ? If Toby knew for the tape, he could have inform Jenna. And killing Charlotte with a rod from Melissa's suicase would be like kill two birds with one stone !
</p><p><i>The girl in Alison's grave</i>: who she could be if Cece was Bethany ? Wren never was part of the A-game I think. Elliott paid him to secure the Cece Drake fake ID (remember the visitor pass) perhaps. Maybe he was in Rosewood only to investigate on the death of a relative one, a blonde girl who had nothing to do with Charlotte, Mary and all the Rosewood drama !? (It could be revealed in a movie, but) My unexpected plot is that Wren's sister is in the grave; Wren will come back this season to reveal that to Mona and Melissa, and get revenge from them !
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</p><p>Sorry for this way too long post, I tried to connect all the characters !
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