Elizabeth Lail, Georgina Haig Elizabeth Lail, Georgina Haig

We've all heard the "Let It Go" jokes by now, but Frozen fever has not yet broken.

When Once Upon a Time returns for its fourth season on Sunday (8/7c, ABC), it will be the residents of Storybrooke, not Arendelle, who will fall under the icy touch of the hit Disney franchise for the first 11 episodes. Fans of the series, however, need not be worried that their favorite characters will be shunted to the side to make way for Anna and Elsa. "Frozen is not taking over our show," co-creator Edward Kitsis assured TVGuide.com. "If you are a fan of Once Upon a Time, we are still continuing all the stories that we left off with last year — with Regina, with Emma, with Snow and Charming, with Rumplestiltskin. Fans should be looking at the Frozen arc similar to the way we did the Wicked Witch or Peter Pan."

Once Upon a Time gets Frozen when Anna and Elsa visit Storybrooke

Fans of Frozen, however, should be thrilled. In flashbacks, we'll see what became of Queen Elsa (Georgina Haig) and how she's preparing for her sister Anna's (Elizabeth Lail) wedding to iceman Kristoff (Scott Michael Foster). "We talked about an ice sculpture with vodka," Kitsis jokes. "No, even though Anna is engaged, for us the thing we love best about Frozen is that it's a story about two sisters. Once Upon a Time will continue with that. The wedding is secondary to the relationship between the sisters."

Those festivities are put on hold when Anna sets out on a journey to discover what their deceased parents were really seeking. Over the first half of the season, Once will explore that ongoing mystery and just how Elsa ended up trapped in Rumplestiltskin's urn, which brought her to Storybrooke.

Although Elsa's exposure to the town's modern trappings will stress her out to the point of creating yet another snow monster, she has in fact gotten more control over her magic. "We will pick up post-movie, and Elsa will have a better handle on it," says Kitsis. "But there's another character on the show who found out she has magic and is having trouble controlling it, and that is Emma Swan. One of the things we're excited about is their friendship. They have so much in common. We saw in Frozen Anna helping Elsa, and we're going to see in Storybrooke Elsa helping Emma."

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That's not the only similarity between the film and the series. "They broke an act of true love between sisters, and on our show we broke our first curse with a mother and a son, so there's definitely some parallels between our show and the movie," he adds.

Enough with the Frozen already! Check out what else Kitsis and co-creator Adam Horowitz had to say about Season 4:

On one hand, Emma (Jennifer Morrison) is harnessing her magic powers, and on the other, she's getting her personal life in order. She and Hook (Colin O'Donogue) will eventually go on a date somewhere other than Granny's. Will we also finally see Hook in some modern civvies?
Edward Kitsis:
He absolutely will have a new modern look for his hot date with Emma Swan. So the audience can look forward to new Hook, but new Hook is not going to show up in a polo shirt and Dockers. He's still going to be rock 'n' roll.

Speaking of romance, fans love Regina (Lana Parrilla) and Robin Hood (Sean Maguire) together. So the question is: How do you solve a problem like Maid Marian?
Adam Horowitz:
You rip her heart out and move on.
Kitsis: For us as writers what we were interested in: How does she react to this now? For Marian, it is one thing to find out that you traveled through time, but it's another thing to find out your husband thought you were dead and just moved on. But it's also another thing to realize the person he moved on with is the person who killed you. So I think there's going to be some trouble in paradise. We're really excited to see Regina deal with that.  At the same time, we're really excited that — we've seen in the past Henry (Jared Gilmore) and Emma in Operation Cobra — this year we are launching a new operation between Regina and Henry that will go the whole year.

There's a picture out there of Sidney Glass (Giancarlo Esposito) and Regina holding hands. Is that just for comfort, is it scheming, a little bit of both?
Some of those pictures have been released out of context. As far as Regina and Sidney go, old habits die hard. We're picking up the relationship between those two characters from where we left, which was way back in Season 1 where she lost her way. We're going to find out what's happened since then with them, what he's up to now and why they are together.

We have to ask about Charming (Josh Dallas) and Snow (Ginnifer Goodwin): Didn't they think it was a little odd to have Emma's brother named Neal after her lover?
Yes, and also they're going to question whether or not they should have gone with Baelfire. Prince Baelfire sounds better than Prince Neal. I think that's something they're going to have to wrestle with in the premiere.

Lest we forget, they are also now sharing only one heart between them. How much will that be explored? Also: There's a black spot on it!
There are some other issues we're going to see in the first half of the season, but that is definitely something that we're aware of and will be explored.

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Moving on to another married couple, what does a Belle (Emilie de Ravin)-and-Rumple (Robert Carlyle) honeymoon look like?
They go to Sandals! Uh, we're going to see their honeymoon in the premiere. It is romantic and very much keeping in the spirit of Beauty and the Beast.

Is that the nod we saw in the trailer to the famous ballroom scene? How psyched were you to get Belle and Rumple into those duds?
It's fun for us to give them some moments of joy that call back some of the most joyous parts of that movie, which we love.

What is Belle's emotional state? She'll be so happy during her honeymoon, but how will she deal with the loss of trust when she finds out about the dagger?
She does trust him. She has no idea what he's doing. The premiere is going to give us some insight into why he hid the dagger from her. We're also going to see Gold set on a new mission. That is something we're going to explore over the first 11 episodes. The other thing we're really excited about is we're showing you a Belle flashback before she met Rumple. We're going to meet her mom (played by guest star Frances O'Connor). We're going to see a little bit of what made her love of books and need to be a hero.

Will Scarlet (Michael Socha) also makes his way to Storybrooke, and his sister died by falling into ice. Is there going to be a connection with Elsa?
Will Scarlet, as we know, his first main thing is that he's a disgraced member of the Merry Men and we know that Robin Hood is now living in Storybrooke. Will is also going to have a connection with someone else. We're going to meet Will, and he's a thief in a town where Emma is the sheriff. We're going to get a little bit of that and a little Robin Hood. The second half of the season is where we're really going to dive more into Will Scarlet. I don't think he has an Arendelle connection, although his sister did fall through ice.

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Where in his timeline will we find him? After he married Anastasia?
We meet him after the events of Once Upon a Time in Wonderland. How he returned to Storybrooke, why he returned to Storybrooke when it seemed like he had such a happy ending with the Red Queen is obviously something we want to explore this year and explain. And if you've never seen Wonderland, do not worry. We will not be telling it in a way where we assume that you've watched all 13 episodes of Wonderland.

What can you tease about Zoso (Brad Dourif) returning?
We're going to be seeing more Dark One lore and history.

Maleficent (Kristin Bauer van Straten) will return in the season's second half. Does this mean Aurora (Sarah Bolger) and Prince Phillip (Julian Morris) will get some screen time?
We're certainly going to be seeing a little bit of Aurora. The Maleficent appearance is not immediate, but when she comes we're excited to delve into her story in a more significant way than we have in the past.

Do you have to spread out your use of CGI dragons on the series?
Absolutely, you can't do CGI dragons every episode, but we have definitely some fun CGI creatures coming your way this year.

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

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