Lana Parrilla, Sean Maguire Lana Parrilla, Sean Maguire

Now that the Snow Queen has counteracted the curse of Shattered Sight, Once Upon a Time is finally ready to let its Frozen story line go.

On the fairy-tale drama's midseason finale on Sunday (8/7c, ABC), we'll see one other benefit of Storybrooke returning to (relative) normalcy: Maid Marian (Christie Laing) will have thawed out after being frozen. That would normally make Robin Hood (Sean Maguire) a merry man, except for the fact that he lost his heart, figuratively, to Regina (Lana Parrilla). "Robin Hood has a difficult choice to make," Parrilla tells TVGuide.com. "He has to choose between these two women. Having a son with one and a history with her, and this newfound love with Regina is a very difficult decision for him. You'll see who ends up choosing this Sunday and what happens."

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The outlaw had initially decided to be noble and stick with his wife, but once Marian turned into a wife-cicle, he put his fidelity on ice as well and started seeing the erstwhile mayor in her dark and apparently alluring lair. So unless there's some sort of divorce loophole in Sherwood Forest, Hood may now feel obligated to go back to the old ball and chain. "Who knows?" Parrilla says with a laugh. "You may see that."

Check out what else Parrilla had to say about the coming Queens of Darkness, searching for The Author and more below:

Will Operation Mongoose be in full effect going forward? That was back-burnered a bit in the first half of the season.
Lana Parrilla:
I think that was intentional. The Author is a very important character, this person or thing or whatever it is, is responsible for everyone's fate. This for Regina has become her No. 1 priority. She is so focused on figuring out who this author is because once she gets ahold of this author, then everything can fall into place for her. Or at least that's how she is hoping it will turn out. And working with Henry (Jared Gilmore) is so fun for her. She loves having this bond with her son. It's not just a mother-son relationship any longer; they're friends. There are no secrets between them, and that's new for Regina. She was always manipulating and hiding something. And now all cards are out on the table. She's so forthright with him. She wants that trust. Also, Henry has the heart of the truest believer, so that's a good person to have on your team. He always has a positive outlook on things, so he's constantly encouraging her and has her back in a way that no one else does, to keep at it and don't give up. He's on board and helping her research and finding the clues. There will be clues that will be revealed in the second part of the season that will help us find who the author is.

Will additional "lost" pages for the storybook be found during this search?
Parrilla:
They're on that journey as well, finding the missing pages and finding the person involved in taking these pages out and replacing them. So that will be revealed as well in the second part of the season.

Mr. Gold/Rumplestiltskin (Robert Carlyle) intends to leave Storybrooke, but does not seem to have good intentions for the rest of the world. Can you tease anything about his journey in the second half of the season?
Parrilla:
I can't say anything about Gold or where he's headed. I will say that however he's going about this plan, Regina doesn't think it will work out. She has very little faith and she's a bit delusional about this thing too. She doesn't quite know that part of his plan is taking her son away. So we'll see how that unfolds.

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During the Shattered Sight curse, Regina got to revert back to being the Evil Queen. Did that feel good for that brief period of time?
Parrilla:
She's the best. It was fantastic. I loved everything about it. It was so fun.

Is that outfit comfortable?
Parrilla:
It's never comfortable nor is it ever warm. They have to make the costume a half inch bigger than my normal size when it's during the winter months so we can layer up underneath. I wouldn't say they're comfortable but I'd say they're extremely beautiful and glamorous to look at.

Speaking of well-dressed female villains, what can you tease about the Queens of Darkness — Maleficent, Ursula and Cruella de Vil (Kristin Bauer van Straten, Merrin Dungey, Victoria Smurfit) — coming to Storybrooke?
Parrilla:
They are all fabulous. They are villains that we love and have been dying to see come on to the show. Some of us have a history with these characters, so I would say that Rumple has a history with every single person. He definitely has history with these women as does Regina.

Maleficent is Regina's frenemy...
Parrilla:
I would say they're more friends. I would say they became enemies when Regina needed something from her and ended up stealing it from her, which is the Dark Curse. Regina and Maleficent have a really interesting history and so there's an episode where you'll see how they met and how they became friends. We start [shooting] on Thursday. I'm so excited about it.

Who has the best outfit of the Queens?
Parrilla:
Oh gosh. You know what, this is a tough choice because everyone has different tastes. A couple times I have stumbled into the wardrobe department and have been like, "Oh my God! Is this my next costume?!" And they're like, "Nope, that's Maleficent's." I'm like, "Damn! It's so awesome. Why didn't you guys make this one for me?" But my favorite has been Cruella. I love her costumes probably because I wear black so much. But the black and white combo with the hint of red is to me so chic and fabulous. And those are her three colors predominantly. Cruella looks amazing. You're just going to love her costume.

How do you think Robin Hood will get out of his predicament? And what are the Queens of Darkness doing in Storybrooke? Share your theories and predictions below.

Once Upon a Time airs Sunday at 8/7c on ABC.
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