Our world was turned upside down on Pretty Little Liars Season 3, Episode 12: “The Lady Killer,” when we learned Toby (Keegan Allen) is on the "A" team.

While we know the truth, the Liars don't, and since the audience isn't able to reach through the TV and drop them a note, they're going to be in the dark for a bit. However, we do know his secret won't be kept forever.

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On Season 3, Episode 16: "Misery Loves Company," one of the Liars will learn the truth, and according to showrunner Marlene King, "the fallout will be huge."

But which Little Liar will be the first to find out? We're going to speculate about why each Liar might be the first to know, and think about whether or not we want them to have that pivotal role. We've already looked at why Emily (Shay Mitchell) might be the unlucky one, and now we're going to break down why it could be Hanna (Ashley Benson) instead.

On Season 3, Episode 16: "Misery Loves Company," one of the Liars will learn the truth, and according to showrunner Marlene King, "the fallout will be huge."

But which Little Liar will be the first to find out? We're going to speculate on why each Liar might be the first to know, and think about whether or not we want them to have that pivotal role. We've already looked at why Emily (Shay Mitchell) might be the unlucky one, and now we're going to break down why it could be Hanna (Ashley Benson) instead.

Why she might be the first to know: Ever since she found out that Mona (Janel Parrish) was "A", Hanna has actually been one of the most gung-ho "A" investigators. She wants "A" taken down so she and Caleb (Tyler Blackburn) can be left alone. It's possible she'll follow a trail of clues that leads her straight to Toby. This seems even more likely if Caleb ends up helping her investigate, since the "A" team might not have properly accounted for his tech savvy.

Why this would be interesting: Hanna knows better than anyone how much it hurts to have someone you love and trust turn out to be on the "A" team, so we'd be interested to see how she'd approach Spencer (Troian Bellisario) with this info. Also, if Caleb helped her discover this info (or even if she just tells him before the other Liars), this would be a good way to keep him roped in to the main plot.

Why we don't want it. Hanna doesn't have much of a bond with Toby, so her finding out wouldn't have the same emotional impact as if it were Spencer or Emily. Plus, she already has a ton going on, what with Caleb being shot and Mona being on the "A" team.

What do you think: Do you want Hanna to be the first to find out?

Find more Pretty Little Liars spoilers here.

Don’t miss the next new episode of PLL, the Halloween special, on Tuesday, October 23 at 8 p.m. ET/PT on ABC Family.

Rebecca Martin is an editor at Wetpaint Entertainment. Follow her on Twitter @BeccaMartin47.

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