'Once Upon a Time' Season 4 Spoilers: Who will Play Princess Elsa?

When season three of "Once Upon a Time" ended in May, fans were shocked to see Princess Elsa of "Frozen" in the fairytale drama.

Although it is yet to be revealed who will enact the role of Elsa, Anna Faith Carlson, 18, who took social networking sites by storm after she started posting side-by-side pictures of herself with Elsa online, hopes to bag the role.

"I know this is kinda a lot to ask, but it would mean the world to me. Can you take a picture from my page dressed as Elsa, post it and hashtag the words #AnnaAsElsa? I'm hoping to audition as Elsa on 'Once Upon A Time'! You can do it on Instagram and/or Twitter. :) THANK YOU SO MUCH!" she wrote on Instagram.

Besides Elsa, her sister Anna and pal Kristoff will also be joining the "Once Upon a Time" cast.

Elsa is expected to appear in nine episodes, and showrunners want to keep the characters as close to their animated counterparts as possible.

"We're not going to redo the movie, because we just don't feel like it's in anyone's interest for us to redo it," Once Upon a Time producer Adam Horowitz told E! News.

"But what we are going to do, we're not ready to tell you. But what we can say is we're very aware of what we think makes this character from 'Frozen' so special and we want to honor that and make sure that what we do is in the universe of (what) everyone fell in love with this past year."

In the meantime, fans of Elsa have already started speculating about who will play the ice queen's role.

Idina Menzel, who voiced Elsa in the hit 2013 Disney animated film, is a favorite. "We have an offer out to Adele Dazeem (Idina Menzel) to play Elsa," Horowitz revealed to Entertainment Weekly soon after the show's season three finale aired.

"Once Upon a Time" co-creators Eddy Kitsis said that the first half of the next season will take place in Storybrooke, despite a number of "Frozen" characters making their way to the show.

"I don't want to say anything definitive, but we are not looking to in, like episode 3, go, 'Oh my God, we're not on Mars,'" joked Kitsis. "As always on the show, we like to show you different worlds. I would be let down if we don't get to see Arendelle," he added.