Who Is Lesli Stone On 'Pretty Little Liars'? Mona's Friend Is Back For Season 6 & Possibly Up To No Good

Do you happen to remember Mona's bespectacled, red-headed friend Lesli Stone from Pretty Little Liars Season 5? She turned up for the first time after Mona's "death," and didn't come back until it was time to act as a key witness against Ali and the Liars. Well, as it would turn out, she's back in Rosewood in this week's "She's No Angel," and she's not happy. It would seem that when Mona turned out to be alive, Lesli got tangled up in all of the fallout of the legal drama (and judging by the fact that she threatened Mona and called her a "conniving little b**ch," she's out for blood).

But who is she, again? (Hey, it can be tough to keep track of all of the suspicious peeps on Pretty Little Liars). Well, we met her for the first time back in "Oh, What Hard Luck Stories They All Hand Me." She was visiting Rosewood for the weekend, claiming to be there as support for Mona's mother during "that awful girl's trial." When the Liars asked about her history with Mona, Lesli gave them a vague answer about Mona's grandparents house during the summer, and it was fishy enough to set the Liars collective truth-o-meters off. Then, when Emily casually brought up the fact that she rather conspicuously did not attend Mona's funeral, Lesli waved her off with a weak alibi about a college exam (which was basically as suspicious as her purported history with Mona).

Later in the same episode, things got even more fishy — Lesli borrowed Mona's collection of Poe stories (you know, the one that we later found out held a hidden audio tape of Bethany railing against Ali in a therapy session), which caused Aria's brother Mike to totally flip out. Long story short, Lesli totally spun the story in her direction. She claimed that Mike was the jealous, controlling boyfriend type, deftly implying that he was the killer.

Lesli popped up again a few episodes later in "I'm a Good Girl, I Am" and she basically only got worse. She acted as a witness in Ali's trial, producing a very key piece of evidence — a letter revealing that Ali had threatened Mona two weeks before her "death." Oh, and she was just as squirrelly when the judge asked her why she hadn't stepped forward with the incriminating evidence sooner, and she claimed to have misplaced the letter, only to mysteriously find it just in time for the trial. Suspicious much?

She then went on to implicate the Liars in her testimony, citing their touchiness and Mike's strange outburst, and she even went so far as to accuse Hanna of stalking her, which was basically a nail in Hanna's coffin (in case you need a refresher, this was back when A was busy framing Hanna as Ali's accomplice in Mona's murder). Ouch.

TL;DR, Lesli has always been suspicious, but now that we know A/Charles framed Mona for Ali's murder, it only brings up even more red flags. Does this mean Lesli's been working with A this whole time? She's always had (and will likely continue to have) murky motives, and it's probably best if the Liars keep her at arms' length during her visit to Rosewood. I mean, after all, we still have absolutely no idea who she is, or what she wants (or why she wants it) — but I have a feeling it's not good. For more theories, check out Bustle's Pretty Little Liars podcast below.

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