The big reveal that Toby (Keegan Allen) is on the “A” team was one of the most shocking moments in Pretty Little Liars history. On the Season 3 summer finale (Season 3, Episode 12: “The Lady Killer”), all of our feelings about Spencer’s (Troian Bellisario) leading man changed in an instant. Why would he want to torture, attack, and attempt to murder the Liars?

We’ve written up our own ideas on how long Toby has been working with “A” (which you can read here), but let’s review all the possible reasons he could have for being on the team in the first place.

Alison. As fans know, Alison (Sasha Pieterse) claimed that Toby was spying on her and her friends in Season 1. As a result, the Little Liars were always suspicious of him, and suspected him of killing Ali early on. We never actually got definitive proof that Toby had been spying on the girls, but Alison was powerful enough to turn her friends against him with that one claim. Toby (and the “A” team) could hate Ali’s friends merely by extension, or because they think the Liars are just like her.

Credit: ABC Family

The Jenna Thing. Alison got the Liars to pull a prank with her at the Cavanaughs’ house, which became known as “the Jenna thing.” Alison said they were going to throw firecrackers at Toby andJenna (Tammin Sursok) while they were making out in their garage, which ended up blinding Jenna. If Toby is still in love with Jenna, or if he was just deeply wounded by such a vicious attack, we could see why he would want to hurt Ali and the Liars in return. 

Turning him into a social pariah. Even if Toby only hated Alison in the beginning, it would be completely understandable if he began hating the Liars after his bloody sweater was discovered by the police, sending him to jail. Since the sweater was found at Ali’s house, he probably figured it was the Liars who turned it in. After the evidence turned out to be corrupted, Toby was mocked in public everywhere he went, and little kids even threw stones at him.

They know about him and Jenna. We don’t know how, but Alison somehow found out about Toby and Jenna’s sexual relationship in the past. That’s how she bought his silence after the firecrackers incident, by threatening to go public with the information. But she did tell the Liars. If the Liars are the only ones who know about it (and especially if Toby is still in love with Jenna and wants to eventually go public with her), then he would want to keep them silent at all costs. 

Emily’s rejection early on. It’s a long shot, but Toby seemed to have his sights set on Emily (Shay Mitchell) at the start of the show. He even made her a mix CD. But Emily, obviously, was never going to reciprocate romantic feelings, and this may have turned an already mentally disturbed head case into a mentally disturbed head case with a target. 

What else can you think of?

Catch the PLL Halloween special on Tuesday, October 23 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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