'Once Upon a Time' Officially Confirms 'Frozen' Story line, Fans React on Twitter #FrozenIsComing

Once Upon a Time went out in a big way last night.

During the two hour season finale, Once revealed a new character for season four, and possibly a new villain for Storybrooke.

In the final two minutes of the season three finale, we see a mysterious person starting to form from a liquid that starts spilling out from an Urn. As the blob begins to form into a person, fans were literally Frozen in place after realizing that the new character would be Queen Elsa from Disney's Frozen.

Click here to read the full recap of last night's episode.

Once Upon a Time posted the following official photo to their Facebook page confirming the news.

After fans picked their jaws up off the floor, they took to Twitter to express their shock using the hashtag #FrozenIsComing.

@daninunley31709 tweets "I can't contain my excitement. Elsa in Storybrooke. #onceuponatime #frozenIsComing

@KayBreM writes "Just when I start to think this show had nowhere else to go. #frozenIsComing #onceuponatime"

@AndySwift tweets "I keep playing Elsa's entrance from last night's #Onceuponatime over & over in my head. Still Trying to grasp that concept. #FrozenIsComing

@EzzyNYC writes "So apparently, @OnceABC is going to do the Frozen story line next season. Why can't people just "Let It Go" already? #FrozenIsComing"

@EmmaRoseSwan tweets "OMG! OMG! OMG! OMG! OMG! OMG! OMG! OMG! OMG! OMG! OMG! OMG! OMG! OMG! #FrozenIsComing OMG! I'M GONNA DIE!"

@joeyyyx14 writes "Everyone thought Frozen was done, GUESS AGAIN!?!?! Frozen comes back on top, colder than ever before #FrozenIsComing."

@_SarahABuckley writes "Elsa? Do you wanna build a snowman? #OnceUponATime #OnceUponATimeSeasonFinale #OnceFinale #OUATSeasonFinale #FrozenIsComing."

Now the most important question of all, who would you want to see play Elsa on the TV series? Let us know in the comments below.