Demon baby! Is that a subtle message to Emma (Jennifer Morrison)? (We kid.)

Yesterday, Once Upon a Time star Ginnifer Goodwin (Mary Margaret/Snow White) shared this very professional-looking photo of her Halloween costume, tweeting, "Calling all #OnceUponATime crew members! Don't forget today's costume contest. I will be awarding prizes at wrap!"

But who is she? When someone guessed that she was dressed as Mia Farrow from Rosemary's Baby, Ginny replied, "ding ding ding!" Nice!

This costume is pretty spot on, actually. Mia's short blonde hair in this classic horror film set the standard for pixie cuts, and Ginny is now rocking the cutest cut on TV. And that blue nightgown is a pretty good match for Rosemary’s outfit in the film. The doll, though — that thing is freaky as hell!

Catch the next new episode of Once Upon a Time on Sunday, November 4 at 8 p.m. ET/PT on ABC.

Source: @GinnyGoodwin

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