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Theories About Mona That 'PLL' Fans Will Love

The penultimate episode of Pretty Little Liars is upon us and Mona has become the number one suspect as A.D., but is she really Uber A? Most fans agree she's just another red herring — but if that's the case, why are all signs pointing to her? Is she really just trying to help the Liars or has she been on A.D.'s side this whole time? There are so many theories about Mona on Pretty Little Liars that it's clear no one really knows what's going on anymore. One thing's for certain though, Mona's definitely up to something.

In the past two episodes, Mona has been acting very suspicious. First, it was revealed that Mona has built a lair in her apartment, which includes pictures of the board game and the shovels the Liars used to bury Archer. Then, things got even sketchier when Caleb traced the IP address of the game to Mona's apartment and showed her staring at the game in admiration. Either A.D. is setting Mona up or she's got some serious explaining to do. If you have no idea what could be happening with Mona, here are just a few theories about what she's possibly been up to and where she may end up when the show comes to a close.

Mona Set Up Aria To Get Caught

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Reddit user Kate1496 suggests that Mona isn't A.D. or working for them, but thinks that Mona actually just set up Aria by leaving that flip phone for her to find in the latest episode. That's why, unlike the other times A.D. talked to Aria, there was no creepy video chat. Plus, it seems highly unlikely that Mona would've been able to listen into the call if it really was A.D. Mona knew she'd need hard evidence that Aria was working with A.D., so she set Aria up in order to get it.

Mona Killed Charlotte

This week's episode will (finally!) reveal Charlotte's killer and Reddit user kevyn123 is sure it's Mona. For one, Mona looked guilty leaving Charlotte's funeral and she has mentioned that she's "gotten blood on her hands" trying to save the Liars. Thankfully, fans won't have to wait long to see if this theory is true.

Mona Has a Twin

While most fans are convinced Spencer has a twin, Reddit user orbitsource has an alternative theory. They believe "Geek Mona" and Mona are actually twins and that's why she put her glasses on at the end of the most recent episode; because she's not really Mona, she's the twin. And if you're wondering when they switched, BadWolfIdris has an answer for that too. They believe when there was the fakeout about Mona being dead, the real Mona actually did die, and that's when Geek Mona took her place. Crazy!

Mona Will Die

For those that don't think Mona's already dead, there's plenty of theories that suggest Mona will die before the series end, especially after the above promo was released. A special titled, "Dead Liars Tell All," is to air after the PLL series finale and many believe the woman closet to the left is Mona, which means she'll die before the end of PLL.

Mona's A.D.

While everyone seems to agree with the idea that Mona is a red herring, you never really know with show creator I. Marlene King. Plus, executive producer Charlie Craig previously said that the identity of A.D. would be "nailed down" in Episode 18, which ended with Mona looking at the board game. Really, A.D.'s identity may have been staring fans in the face this whole time.

Find out which of these PLL theories pan out when the final episodes air on Tuesdays at 8 p.m. ET on Freeform.