In the final scenes of Pretty Little Liars Season 3, Episode 5: “That Girl is Poison”, Emily (Shay Mitchell) and Aria (Lucy Hale) realized that someone had drugged Emily with Milizopam on the night that Emily found herself standing over Alison’s (Sasha Pieterse) empty grave (Season 3, Episode 1: “It Happened ‘That Night’”). So how did that someone get the drugs in Emily’s flask, and why?

It seems pretty clear that someone connected to the “A” team planned an elaborate frame job “that night.” By drugging Emily with a memory-erasing pill, combined with alcohol, they assured that Emily wouldn’t be able to remember how she wound up at Ali’s grave.

That same someone (or group of people) used Emily’s phone to contact the Little Liars so that they would be at the scene of the crime as well. Then, this same someone arranged to take pictures of the girls there, effectively framing them for the whole incident. So who planned this whole scheme?

Let’s start with what we know. Jenna (Tammin Sursok) was the one driving the car that took Emily to the graveyard. Emily is starting to remember things from that night, and she now thinks that someone else was in the car with Jenna (as we suspected). 

We also know that Lucas (Brendan Robinson) was seen leaving the photography studio the same night, and heading to his own car. Plus, Aria found the bottle of Milizopam in Lucas’s camera bag, meaning he could have been the one taking the incriminating photos of the Little Liars that night, and had access to the drugs that put Emily in such a stupor. 

Then there’s the fact that we saw Jenna and Lucas together in the Season 2 finale (Season 2, Episode 25: “UnmAsked”). So who could the mystery person sitting shotgun in Jenna’s car that night be? Is itMelissa (Torrey DeVitto), who Jenna and Lucas were seen talking to intensely at the Masquerade Ball? Or is it the new “A,” who was seen going through Maya’s (Bianca Lawson) bag in the final scene of “That Girl Is Poison”?

Share your theories on who was involved with setting up the Liars in the comments below!

Catch an all-new episode of PLL on Tuesday, July 17 at 8 p.m. ET/PT on ABC Family.

Molly Friedman is an editor at Wetpaint Entertainment. Follow her on Twitter @MollyFriedman.

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