Once Upon a Time fans get ready, because ABC teased that more "Frozen" characters will appear on the show as Queen Elsa made a surprise appearance at the end of the Season Finale! Will Idina Menzel and Kristen Bell play Elsa and Anna in the show?

For those who are not familiar with the series, Once Upon a Time is a fairy tale fantasy drama produced by ABC that takes place in fictional seaside town of Storybrooke, whose residents are actually characters from various fairy tales that reincarnated to the real world and are robbed of their memories courtesy of the powerful curse by the Evil Queen.

Once Upon a Time stars Jennifer Morrison as Emma Swan the daughter of Snow White and Prince Charming, nicknamed "the Savior", and along with her Ginnifer Goodwin as Mary Margaret Blanchard/Snow White, Josh Dallas as David Nolan/ Prince Charming, Robert Caryle as Mr. Gold/ Rumplestilskin, and Lana Parilla as Regina Mills/ the Evil Queen.

During the season 3 finale on Sunday night, Elsa from Frozen made a surprise appearance. Near the very end of the episode, a blue fluid spills out of an urn and starts to fill a symbol carved in stone in a barn's floor. After the symbol is filled, the blue fluid forms into a woman's shape. The woman has blonde hair and is wearing a blue gown and blue gloves. She removes one of the gloves and fires an ice blast. The woman exits through the barn doors leaving behind a trail of ice and frost on her way.

While the woman's face was not shown during the episode, it was very clear from what was shown that it was Elsa from Frozen.

Rumors have started to spread that the voice behind Queen Elsa Idina Menzel will be cast in Season 4 even though it is not yet been confirmed or discussed by ABC and Walt Disney in terms of rights. The shows producers, Edwar Kitsis and Adam Horowitz mentioned that they wanted Elsa and her younger sister Anna in the show and wants both Idina Menzel and Kristen Bell to reprise both characters again.

"We would be completely honored if Kristen Bell or Idina Menzel wanted to do our show."

Kristen Bell expressed her opinion on having Frozen characters appearing in the show by saying:

"That would be unbelievable," she said. "I love that character of Anna so much. She is exactly who I wanted to see when I was five years old. She is really close to my heart."

It looks like fans of the series will be excited to see both Elsa and Ana in Storybrooke as the season 4 of the show is scheduled to air sometime in the Fall of 2014.

So what do you think of Frozen characters being added to season 4? Sound off in the comments below!