When "A" is in charge, a prom can be the perfect setting for a tragic death.

There's nothing like a prom to stir up the tension. Before breaking down all that happened in Pretty Little Liars: Original Sin Episode 2, here are some things to remember about the pilot: When all the new liars were united in detention during the episode's final scene, they came to the conclusion that the person behind all the evil claims against them was Karen (Mallory Bechtel). Their anger towards the mean girl is what propels them to join forces for the first time and pay back all the damage she allegedly caused them. Imogen (Bailee Madison) even utters the phrase "we should kill Karen Beasley," which foreshadows the climactic moment at the end of Episode 2. After all, when A is in charge, a prom can be the perfect setting for a tragic death in the PLL universe.

Episode 2, titled "The Spirit Queen," starts with a flashback from 6 months before the vengeful alliance, when Imogen and Karen were still best friends. As they party it up in Karen's house and drink a lot of beer, things quickly shift gears when Kelly (Karen's equally evil twin sister) reveals that she spotted Imogen kissing Karen's boyfriend Greg (Elias Kacavas). Once she finds out about this, Karen blows up at the party and expels Imogen, even though the latter tries to justify that Greg was the one who stole a kiss without her concent. This helps viewers to contextualize the sudden friends to enemies change and understand why the popular mean girl had reasons to detest Imogen.

RELATED: 'Pretty Little Liars: Original Sin' Review: Finally, a Spinoff That Could Last

Heading back to the present, the girls decide to screen a compromising video of Karen before the Jordan Peele double feature event that Tabby (Chandler Kinney) is hosting for the student body. Although they aren't sure whether to stick to the plan, they all agree to move forward after the liars receive anonymous videos showing someone wearing gloves and destroying Karen's Spirit Queen campaign posters, inserting a razor blade into the mean girl's ballet shoe, manipulating Noa's (Maia Reficco) pee cup, and showing a mouse being tortured. The videos sent alongside texts that seem to be written by Karen herself are enough for the group to determine that the revenge video planned for the screening isn't nearly as awful as her evil actions.

On Thursday, Imogen, Noa, Tabby, Faran (Zaria Simone), and Mouse (Malia Pyles) distribute flyers throughout the school promoting the film event and Karen decides to attend it just to make sure that her opponent in the Spirit Queen race doesn't take away her crown. After editing Karen's video, Tabby convinces her male best friend Chip (Carson Rowland) to play it before the screening; in return, she agrees to be his date to the prom. When the time comes for all the students to sit down at the theater, they are surprised by what seems to be a little promo for Karen to be crowned queen. Yet, when the mean girl appears on the screen completely wasted and trash talking Imogen and Greg, the embarrassment is instantaneous. The video ends at a point where it seems that Karen will strip in front of the camera, but in reality, Imogen intervened that night and stole Tyler's (Brian Altemus) phone before her former friend did something she would regret in the future, which is how she came by the video in the first place.

After the screening, Tabby almost gets into trouble with her manager Wes (Derek Klena) for convincing Chip to show the video of Karen at the theater. However, given the fact that Wes is clearly interested in having a fling with Tabby, he brushes off the incident. Later that night, Imogen receives a text message from Karen to meet her in the cemetery, which she does. During their candid conversation, Karen reveals that the reason why she was so upset about the kiss was because she had lost her virginity to Greg that same night. Imogen feels remorse for keeping Tyler's phone with the video for so long and becoming the mean girl that her mother warned her not to be.

The next day, Kelly pretends she is Karen and heads to the principal's office to withdraw her name from the Spirit Queen race. This means that Imogen will be the only candidate for the crown, making her the winner by default. The principal shares the news with Imogen, uttering the phrase, "like mother, like daughter." This hurts Imogen's conscience even more since in her mind, her mother was deserving of the crown — yet, as viewers know from the 1999 party, Davie wasn't the best example of a kind and caring person during her high school years.

In an attempt to comfort and support their friend, Tabby, Noa, Faran, and Mouse decide to go to the prom with Imogen. Since Noa apparently caught Sheriff Beasley (Eric Johnson), the police officer in charge of overseeing her community service (and Karen and Kelly's father), in a compromising situation, she is able to convince him to let her attend the prom in exchange for keeping his secret. While everyone seems to be having an amazing time on the dance floor, Imogen wants to find Karen and apologize for her actions. Little does she know that what Kelly did as Karen wasn't to be nice, but instead to help her sister humiliate Imogen in a Carrie-like manner. When Imogen steps on stage to receive her crown, Karen is up on the balcony getting ready to spill paint on her, but the masked individual wearing a jumpsuit shows up and pushes Karen to her death. The mean girl dies similarly to Angela at the 1999 rave, and all the liars receive a threatening text message from "A" (this is the first time that the anonymous number signs off as the well-known villain). The message says: "To thine own self to be true. One bully down. Five more to go. Keep quiet about me or you're next."

To conclude this dramatic turn of events in Millwood, we must note that A is even more vicious in the spin-off than the OG series, and there is one more suspect to think about with regard to the identity behind all the texts and kills. Since Karen and Kelly swapped places in this episode, this could mean that they might have swapped places at the prom too. As of now, we know that one of the twins was killed, but we aren't certain which one was the victim. Yet, one thing is clear as crystal — the more we progress into the story of Pretty Little Liars: Original Sin, the more people will be added to the list of potential characters behind the killer persona of A.

Isabella Soares is a Freelance Resource Writer for Collider. She is passionate about teen dramas, Glee, and simply anything with a plot twist. Aside from Collider, Isabella has been featured in Foreign Press USA, Stylus Magazine, the Winnipeg Free Press, The Uniter, and Empoword Journalism.

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