Elsa

Elsa, also known as the Ice Queen, is a mysterious woman from the Enchanted Forest who has the magical ability to create and control ice and snow. For unknown reasons, she ended up banished into a prison made by Rumplestiltskin, but now she's out and ready to wreak havoc in Storybrooke... and perhaps exact some revenge.

Before the Curse
In Arendelle, Anna and Elsa place flowers at their parents' grave markers. Elsa assures Anna that they would be proud of her, and Anna says that they would be proud of both of them. Elsa says that she has a surprise for her wedding and leads her back. She takes Anna into the palace to show her the surprise: their mother's wedding dress. Anna hesitantly touches it and Elsa insists that she wear it for her wedding, giving her a necklace to wear with it. As Anna tries it on, Elsa looks around and notices a book on her parents' desk. Opening it, she realizes that it's her mother's diary. Anna comes out in the dress and notices that snow is filling the air. She asks what's wrong and Elsa says that their parents' death was her fault. She runs out and Anna goes after her. Anna catches up to Elsa in the forest and asks what is wrong. Elsa finally tells her that their parents didn't go off on a diplomatic mission as they thought. Anna reads the diary and in it their mother says that they have to figure out a way to stop Elsa's powers. She doesn't believe it and points out that it doesn't say where they were going or what they had planned. Elsa doesn't believe it and apologizes, and Anna insists that she's not a monster and will prove it. Anna takes Elsa to the troll field over Elsa's objections, and calls to Grand Pabbie. Anna asks what her parents were really doing on the voyage. Grand Pabbie doesn't know but he says that he knows that they were going a land called Misthaven. After Grand Pabbie goes back to sleep, Anna asks for two weeks to go to Misthaven. Elsa says that her parents said the same thing and walks away. Later, after Kristoff reveals Anna's plan to her, Elsa goes to the dock and realizes that Anna's ship has left. Kristoff assures her that Anna will be fine. Elsa worries that Anna acts before she thinks and worries that they don't know anything about Misthaven.

Season 3
"Well you just better hope to hell you didn't bring anything else back."

- Regina Mills

When Rumplestiltskin is unable to return Emma Swan and Captain Hook, who have fallen through a portal to the past, back to their correct place in time, he simply locks them away in his vault full of magical things that even he, the Dark One, is unable to comprehend or understand. Whilst trapped, Hook begins to look around and picks up the urn containing Elsa, however, Emma tells him to put it down in case it's dangerous. The pirate is soon able to help Emma realize that Storybrooke - the town in Maine to which they're trying to return - is her home, her magic resurfaces and she's able to power a magic wand that's capable of performing any magic that's ever been accomplished. With this, she opens a portal to the future, and the urn is last seen shaking atop one of the vault's surfaces when this occurs. Soon enough, Emma and Hook are back home, but they take Marian with them, having saved her from being executed by Queen Regina, and the formerly Evil Queen is less than happy to see her new boyfriend's supposedly deceased wife's life has been saved. She tells Emma, who she views as responsible, that she better hope she didn't bring anything else back with her, but across town, it's revealed that the urn managed to make its way through the portal. The lid bursts open, and a blue liquid pours out, filling in the markings left behind by the defeated Wicked Witch. The blue liquid begins to rise into a human form, and before long, Elsa emerges. The Ice Queen removes her glove and uses her ice magic to destroy her former prison, going on to exit the barn with extreme haste, leaving behind a trail of frozen ground.

Season 4
"Don't worry, Anna... I will find you."

Elsa leaves Zelena's barn and begins to explore Storybrooke, accidentally freezing a car when it nearly runs her over. When people hear of this event, they see one of her ice trails and begin following her with it, leading her to run away and hide, creating a giant snow monster in the process. This keeps her chasers dealt wit for a while and, as Elsa hides, a newspaper with Rumplestiltskin and Belle's wedding announcement blows past, and so she decides to search for Mr. Gold Pawnbroker & Antiquities Dealer. When she finds it, she breaks the lock with her ice magic and finds inside the necklace she gave to Anna the day before her wedding day. She vows to find her sister.

Origins
The character of Elsa is based on the main antagonist of classic children's tale: The Snow Queen, written by Hans Christian Anderson and first published in 1844. The story focuses on the struggle between good an evil as experienced by a little boy and girl, Kai and Gerda, who go up against, outwit and ultimately defeat the villainous Snow Queen, who has the magical ability to control ice and snow. This story was loosely adapted into a 2013 Disney film re-titled Frozen, which is the version followed most closely by Once Upon a Time. In this adaptation, the Snow Queen is given a name - Elsa - and is presented in an entirely different way, being an antihero as opposed to a villain and having to deal with her kingdom's discrimination when her unwanted powers are inevitably revealed. Ultimately, however, Elsa accepts who she is and becomes comfortable with the magic she's been blessed with, learning to control it with love instead of fear, and a happy ending ensues as she takes her rightful place as the beloved monarch.

Gallery
Gallery of photographic stills used to promote the character.