The most recent episode of "Pretty Little Liars," ABC Family's addictive murder mystery, had a lot going on -- creepy dolls, some long-awaited statutory rape and a new relationship (seriously, who hasn't Melissa hooked up with at this point?) -- but the second season finale, set to air this Monday night, is sure to contain even more shenanigans. The biggest of which is the highly-anticipated unmasking of the Liars' torturous bully: A.
Over the course of almost 50 episodes, the mysterious A has wreaked a serious amount of havoc (blackmailing therapists, faking suicide notes, attempted vehicular manslaughter, etc.) and the Liars have burned through just as many potential culprits. Except, that is, the one person who probably should be at the top of the suspect list: queen bee Mona Vanderwaal.
Mona has, for the most part, flown under the radar. She's just Hanna's bitchy friend who didn't get along with the other Liars and never merited much in the way of plot (though who can forget her "glamping" birthday). Despite this, or perhaps because of it, she should be considered a prime suspect.
Before Alison died, a then-unpopular Mona was tormented by her and the rest of the Liars were more or less complicit. Mona definitely has a motive for revenge, which could explain her pulling an Emily Thorne, remaking herself in Alison's own image, and ascending the throne atop the social food chain. She even went so far as to start talking like Alison, calling Lucas 'Hermie,' for example --just as A apes Alison in her threats.
Mona's nouveau riche popularity and BFF status with Hanna gave her something that A would need in order to exact her nefarious plot: Access. In this last run of episodes leading up to the finale, her position in the group has risen as she has aligned herself even more with the Liars. She helped Emily get back on the swim team, sacrificed herself to keep A from exposing Hanna's mom and came up with a plot to get the parents off A's trail. New best friends? Not so fast.
Looking at it from a Mona-is-A perspective, all of these actions aren't quite so selfless. Helping Emily? She knows her way around sneaking into the school database -- which Caleb is framed for shortly thereafter. Saving Hanna? She'd have had the police report already if she were A, and by "doing the right thing," she got herself a seat at the Liars' table. Keeping A away from parental scrutiny? Nothing would be more self-serving. Every action is suspect; the old phone she just happened to have laying around when Hanna needed one? Super convenient.
All this evidence notwithstanding, the show has been focused on other suspects: Melissa and Jenna. Melissa seems a likely choice right now because A's plot to get Mona to break up Hanna and Caleb seemingly outed her; but if Mona is A then this is a pretty easy cover-up on her part. Other evidence to the contrary: Spencer's level-headed assumption that Melissa wouldn't have covered up her own fiancé's death. Besides, screwing with the Liars seems like more of a teenage girl's game, and this is clearly a personal vendetta. This leaves Jenna, who, unless she's been pretending to be blind this whole time and not just the last episode, seems like a pretty impossible candidate. Sure, girl is up to no good, but she probably couldn't pull off all of A's plots without the use of her eyes.
There is, however, some behind-the-scenes information to consider. [SPOILER ALERT] In the books of the same name that the show is based on, Mona is A, or at least one of the A's (because there are apparently more than one and the other one is Alison's evil twin or something... it's complicated). The producers have said that their plan was to handle Alison's murder and A's identity differently than in the source material. "Differently," though, does not mean that Mona isn't A, just that the circumstances surrounding the how and why may have altered. It's all still up for grabs.
At the end of the day, Mona may seem like she has the best of intentions, but if we've learned anything about the girls (and guys) living in Rosewood, it's this: Everyone has something to hide.
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