Credit: ABC Photo: STILL: Emma Confronts Snow White About Tamara

There are always plenty of mysteries to be solved on Once Upon a Time, and one of the biggest ones from the last few episodes is about to come into focus in Sunday's Season 2, Episode 20: “The Evil Queen.”

Though fans have suspected that Neal’s fiancee, Tamara, is bad news bears since she first surfaced in Episode 14: “Manhattan,” it wasn’t until she went on a murdering spree of magical beings that we really freaked out. While August Booth/Pinocchio was brought back to life in child form, almost everyone else she has crossed paths with has perished — and now one Storybrooke resident isn’t in the dark about her evil agenda.

In the sneak peek clip below from Sunday’s episode, Emma reveals to Snow White that “Tamara is the ‘she’ August was trying to warn us about!” Surprisingly, her mother’s reaction is far from what she hoped.

After sushing Emma and reminding her that Henry is upstairs, Snow goes into motherly lecture mode, saying, “Look, I know this has been hard for you...” but Emma is quick to correct her.

“This isn’t about me. This is about August — he died trying to warn us about someone, about a woman, ‘she,’” Emma explains. “Tamara has a list of people who live here, what their fairy tale names are. Doesn’t that worry you?”

Umm, it worries us! That list sounds deadly. Though Snow tries to work it out with Emma and explain why that list may exist, it all comes down to Neal. Emma denies that she has feelings for him, but one final word from Snow explains that if she tries to expose Tamara, there could be more than one consequence involving Neal and Henry.

To find out how this heated conversation ends, check out the clip below, and then tune in for OUAT on Sunday, April 28, 2013 at 8 p.m. ET/PT on ABC.

Alyse Whitney is an editor at Wetpaint Entertainment. Follow her on Twitter @AlyseWhitney.