On the Pretty Little Liars Season 3 Halloween episode (Season 3, Episode 13: “This Is a Dark Ride”), Garrett (Yani Gellman) revealed some shocking news about the night Alison (Sasha Pieterse) died. After he and Jenna (Tammin Sursok) had a fight with Ali in her backyard, Garrett went back to the yard alone and saw Alison having an intense conversation with none other than Byron (Chad Lowe), Aria’s father.

The question is, Did Byron actually kill Alison that night?

We only heard a snippet of their conversation, but it was heated. Alison (Sasha Pieterse) told him, “You never paid for your mistakes … You know what I’m capable of.” Byron sounded almost like he was turned on by the situation, saying, “You say all these grown-up things but you’re just a child.”

We didn’t think Byron’s tone sounded threatening, nor did Alison seem scared. They almost seemed like co-conspirators in a cover-up. Ali is presumably referring to Byron’s affair with Meredith as his “mistakes,” and when she says that Byron knows what she’s capable of, she could be referring to how she proved to Aria (Lucy Hale) that he was having the affair.

Credit: ABC Family

One thing is certain: Byron knew where to find Ali when she’d gone missing, and he didn’t speak up at the time. Nor has he spoken up about being with Alison the night she died. Why hasn’t he ever told anyone about this? What is he covering up? Now that everyone, including his family, knows about his affair, and he and Ella (Holly Marie Combs) are heading for a divorce, what else does he have to hide?

One theory is that, after killing Alison, Byron wanted to flee the country so he wouldn’t get caught up in the investigation and possibly become a suspect. That’s why he and his family relocated to Iceland for a year. 

Still, we think it’s possible that he and Alison were talking about something that had nothing to do with her death. Byron may be secretive, but he doesn’t strike us as the murderous type. Tell us what you think in the comments below!

Find more Pretty Little Liars spoilers here.

Catch the return of PLL Season 3 on Tuesday, January 8, 2013 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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