Here's some scoop on Once Upon a Time from Entertainment Weekly's Natalie Abrams' The Spoiler Room column, which was posted on 3/31/17.
What can be teased about the Black Fairy’s return on Once Upon a Time? What is her goal? — AshMarie
Well, that’s the tricky thing. Once the Black Fairy comes back into the picture, her exact motives are unclear to the residents of Storybrooke. “We don’t entirely know,” Jennifer Morrison tells me. “That’s what makes it even scarier. She’s definitely someone that we know has existed in pure darkness for a very long time and has been the root of a lot of the darkness without us having known that she was the initiator of things, so we do know that, but we don’t know exactly what it is that she wants, or what she’s capable of, or the lengths of which she’s capable, so we’re all in a race to find her, deal with her and cut off any resources she has to darkness.”
Link to the full article:Spoiler Room: Scoop on 'Westworld,' 'Grey's,' 'Once Upon a Time' and more