Elizabeth Lail, Scott Michael Foster Elizabeth Lail, Scott Michael Foster

It's getting cold on Once Upon a Time.

The show has cast two characters from the mega-hit Frozen for Season 4, TVGuide.com has confirmed.

Newcomer Elizabeth Lail will come on board as Anna, the younger sister of Queen Elsa, and Scott Michael Foster (Greek) will play Anna's boyfriend Kristoff. There's no word yet on who will play Elsa.

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Anna is a fearless, fun-loving optimist who relies on her resourcefulness to get out of sticky situations, and values her relationship with Elsa above anything else, according to TVLine, which first reported the news. Kristoff is a gruff ice-cutter who's deeply devoted to Anna and Elsa. When their OUAT arc begins, he's slowly adjusting to life at the castle.

Are you looking forward to meeting the new characters? And who should play Elsa?

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