It's taken three seasons, but someone will finally turn on Annalise (Viola Davis) on How to Get Away with Murder.

As this promo promised, Annalise's traitor — who rats her out in the future timeline, leading to her arrest on the night of the house fire — will be revealed on Thursday's episode. This follows the so-called #MurderMutiny in the past timeline, when Annalise lets the Keating 5 rail at her about all her misdeeds and such. (Uh, are you guys also forgetting that she protected your asses too?) If you want to figure out who the snitch is before the big reveal, then pay close attention to this scene and what everyone says.

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But is the snitch and the person #underthesheet one and the same? Maybe Annalise retaliated because the person tattled...

Although someone will betray her, Annalise will also gain a new ally (friend?) this week in none other than Middleton President Hargrove, who will reveal her reasons for being in AA. "Their relationship has been pretty contentious and there's a huge moment between them that kind of changes the direction of their relationship a little bit," Luna (Lauren) Velez, who plays Hargrove, tells TVGuide.com. "There are things that you can assume about her and her journey to becoming president of the university, and this secret will tell you more about why she is the way she is."

Perhaps most tellingly, Velez says that creator Peter Nowalk told her that Annalise and Hargrove "don't have a backstory, so far anyway." "This is a very fresh, new relationship, so I think it surprises Annalise too," she says.

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