Out of all the characters in Pretty Little Liars, Melissa Hastings is definitely an A.D. favorite. She's got the smarts, the skills, the drive, and she's always in the background whenever anything shady is going on. Check out some of our favorite theories on why Melissa might be A.D. below and then tell us if you suspect her using the PLL Suspect Tracker, brought to you by SIMPLE Mobile. And don't worry if you've already voted -- you can change your vote at any time.
1. She's working with Wren.
Wren reappeared in S7E15, and it was a pretty suspicious return. We know that he once cared for Melissa and we know that he also cared for Spencer. What if he is now working with Melissa, but is having doubts about torturing the Liars? He might have met with Spencer to share some information but then chickened out at the last minute. Something doesn't quite add up with the whole "layover from hell" thing.
2. Melissa is also Mary's daughter.
Remember when Spencer first met Mary Drake? She looked at a photo of her with Melissa, and commented on how they could almost be twins. Isn't it a bit strange how two girls with different moms look so much alike? Could Melissa actually be Mary Drake's daughter? Could they be working together to avenge Charlotte's death? It's possible…
3. She hasn't been around recently, but we know she's set to return.
I. Marlene King has promised us that Melissa will return in the last season of PLL, which seems suspicious in itself. We haven't seen her yet and there's only three more episodes to go -- doesn't it seem likely that she might not appear until the very end? And what if she turns out to be A.D.?
4. And while this may not be a theory, we know that she's got what it takes to be A.D.
Melissa is shady, there's no doubt about it. She faked a pregnancy, she was part of the N.A.T. club, she covered up a murder, she was Black Swan, she was one of the Queen of Hearts -- shall we go on? She's been there through ALL of the drama and she's proven to have a dark side. Plus, she is crazy intelligent. We know she has what it takes to be an evil mastermind.
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Do you have any wild A.D. theories about Melissa? Share them with us in the comments below.