While numerous characters from the massively successful Disney movie Frozen will enter the world of Once Upon a Time in Season 4, the show's co-creators are insisting that it won't necessarily turn the show into a Frozen sequel.

Once Upon a Time Season 4 Trailer Shows 'Frozen's Elsa Proclaiming, 'I'm The Queen,' Regina Not Amused

OAUT co-creators and showrunners Adam Horowitz and Edward Kitsis spoke with The Hollywood Reporter for an in-depth look into Season 4 of the series, insisting that the world of Frozen will integrate into the show's world, not take it over.

"What we're trying to do is not make the show just the Frozen show," Horowitz said. "We want to tell this Frozen story, but as you'll see, their story is going to relate to our core characters from Once Upon a Time."

Once Upon a Time's Elsa Creates 'Powerful Snow Monster' To Fight Against Storybrooke Residents

As of now it seems like Elsa (played by Georgina Haig) will have the most interaction with Emma (Jennifer Morrison), Regina (Lana Parrilla) and the gang. The Arendelle Queen enters Storybrooke like a "stranger in a strange land" and introduces a whole new mystery to the series.

"When Elsa arrives, it signifies the start of a mystery that needs to be explored and answered," Horowitz teased. "And the repercussions of that mystery reach out and touch everyone, and you'll see it affects everyone from Regina to Emma to Rumpelstiltskin [Robert Carlyle]."

Elsa is set to take Storybrooke by storm in the Season 4 premiere, titled A Tale of Two Sisters.

The co-creators also discussed the blossoming relationship between Emma and Hook (Colin O'Donoghue) and it seems that the pair aren't getting hitched like Rumple and Belle (Emilie de Ravin) any time soon, if ever.

"There's no chance that Emma - the daughter of Snow White [Ginnifer Goodwin] and Prince Charming [Josh Dallas] - and Captain Hook will ever be a normal couple, but their feelings obviously reached a new boiling point at the end of last season," Horowitz said. "And we're going to continue to explore those feelings, and we're going to continue to explore how they can or can't get closer."

Kitsis added that Emma has "a lifetime of putting up walls, so one kiss does not mean love and [let's] go register at Pottery Barn." He noted that old rivalries will be starting back up again for Hook, including his rivalry with Rumple.

Once Upon a Time returns for Season 4 on Sunday, Sept. 28 at 8 p.m. ET/PT on ABC.

Watch the Season 4 promo for Once Upon a Time here: