Once Upon a Time casts Georgina Haig (Fringe) as the Queen of Arendale, Elsa. The story surrounding these characters will take place post-Frozen with Elsa keeping her powers in check through the love and bond she has with her sister, Anna. However she is still very aware of how much of a threat she can be if she loses control again. Once Upon A Time co-creator, Adam Horowitz:
We are very well aware of how beloved [Frozen] is, so we’re very careful that we want to tell a story that is uniquely ours but also honors those characters that everyone fell in love with this past year.
The thing we love about Elsa is she is perceived to be a villain but is clearly misunderstood, and that goes to the heart of our show.