Mary Margaret may wanna take cover this Sunday on Once Upon a Time.

Following her actions on "The Miller's Daughter," this not-so-innocent heroine will be the target of Regina's wrath on "Welcome to Storybrooke," as teased in this Once Upon a Time promo for the episode.

Elsewhere on this special installment, we'll flashback to 1983, when the curse first hit the town - and we'll be reunited with Jamie Dornan as Graham! We'll also meet a mysterious stranger (played by John Pyper-Ferguson), who looks to get into some fisticuffs with our beloved ex-Sheriff.

Click through photos from the unique hour now:

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