Who is A?

"It would make sense," Lucy agreed. "I mean, she's always kind of, like, missing. It's usually like the three girls and Aria's never there."

The 25-year-old starlet also revealed that she would relish the opportunity to play the villain. "I would love that!" she says."I think that as an actor everyone wants to play the bad guy... it would be fun!"

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Well, we did some digging into this jaw-dropping PLL theory and found TONS of clues that point to Aria being 'A.' You'll have to watch the video above to see all of the clips and proof for yourself, but here's our list:

1. The girls only began receiving text messages from 'A' after Aria returned from Iceland. During a reunion conversation in the pilot episode, Emily and Aria shared they had both been contacted by 'A.' Then, at Ali's funeral, Hanna and Spencer revealed that they too had been getting creepy texts. Does anyone else find the timing of this to be just a tad... convenient?

2. In season 2, Mona even refers to Aria as "Big A" while trying to catch up with her in their high school hallways.

3. The show's creator, Marlene King, is known to give out sporadic hints on Twitter. When a curious fan tweeted her asking for a clue to the true identity of 'A,' Marlene replied with "#BigA." And, that's not the only time that King has alluded to the idea that Aria could be the show's most dangerous character! When another interested fan requested a hint from her on Twitter, she simply replied with a series of emojis consisting of lightning bolts and lips. Yep. Aria has rocked both symbols on her clothing on the show.

4. After Hanna's mom wanted answers about a police report she found while rummaging through Hanna's belongings in episode 2X22, "Father Knows Best," Aria confessed to being 'A' in hopes it would get Ashley Marin and Detective Wilden off their backs.

5. Another giveaway during that episode? The girls all verbally agree that Aria is the best liar.

6. In the season 2 finale, the girls are on the hunt for the "Black Swan" at the masquerade ball after seeing a sketch of the costume in 'A's' lair. Eventually, we find out Melissa was the one behind the mask - but that 'A' told her to wear it. Coincidentally (or not?), Aria is dressed-up in a red and black striped gown at the soiree, a dress that strangely resembles an old Black Swan poster. Again, King shared via Twitter that there was significance to Aria's wardrobe in that episode when a fan tweeted that the dress was "horrid." 

7. Also in the season 2 finale, just before Mona is revealed as the first 'A,' viewers get a glimpse of a dollhouse in the creepy lair. Inside? Dolls representing each of the girls. Ali's doll, which is strategically placed above the other dolls, is rocking a crown. The other girls' counterparts are adorned in threads that match what they wear day-to-day. Aria's doll however, is outfitted in a black 'A'-esque hoodie. Weird.

8. Aria's handwriting on the Halloween train during season 3 resembles 'A's' handwriting... perfectly. Need we explain more?!

9. Aria's anger problem doesn't get past us! First, Aria teams up with Ali to trash her dad's office during a flashback scene. Later, in season 4, Aria goes NUTS inside Ezra's apartment after finding the book he had written about her, Ali's disappearance, and their friends.

10.   And this season, just before the "Fatal Finale," Aria was peeved that her brother brought Mike invited Mona to take Ella's place at the theater. While it's still unclear what Aria whispered to Mona inside the screening, their powder room conversation has us irked! Mona says to Aria, "You are very good, you know just where to put the knife and you're not afraid to twist it... Allison underestimated you." If this isn't a clear foreshadowing of Mona's death, what is?!

11. During that same conversation, Mona also reveals to Aria that she knows about what happened in New York. You know? The fact that Aria accidentally killed Shana! Aria and the liars have gone to great lengths to protect this secret - is it a coincidence that Mona is murdered the following episode?

While we don't know for sure whether or not Aria is 'A,' these clues are definitely giving us some food for thought. The Pretty Little Liars Christmas special, "How The A Stole Christmas," premieres in one week - on Dec. 9, so make sure you tune in to look for some new 'A' clues!

What do you think of this buzzed-about PLL theory? Let @Katie_Krause know on Twitter if you think Aria could really be 'A' or not! And, if you don't think it's plausible, who do you think is the mysterious culprit? Make sure you include that #ETnow hashtag in your tweet!