Georgina Haig

It wasn't easy adapting the hit film Frozen for Once Upon a Time, but it was totally worth it.

"I think that Frozen is a perfect fit for us. Everything was inspired by the animated feature, but is not a direct representation of it," Ginnifer Goodwin told us during a recent visit to Once's Vancouver set.

Go behind the scenes of Once Upon a Time

"It's kind of like doing a historical character, where you have to watch them and figure out how they move or speak," Elizabeth Lail, says. Though the actress, who plays Anna, adds she "probably won't wear braids for a very long time after this."

Find out how Once made Elsa's blue dress and more behind-the-scenes Frozen secrets below.