On the day of Elsa's coronation, Anna enjoys her time outside the castle walls only to be bumped by Han's horse, falling into a raft and nearly falling into the ocean. Despite the rocky start, the two hit it off instantly. Anna waves him to him at the ceremony and he, in turn, catches her as she nearly falls on the dance floor. They talk, enjoy each other's company and get to know each other, as they confess feeling for each other. Hans proposes to her and she accepts.
They go to Elsa for her blessing, but is turned down, explaining to them that they can't marry someone they just met. They plead for her to reconsider, escalating into an argument between the two sisters, only for Elsa's powers to reveal themselves to everyone.
Anna gets her horse and leaves to talk Anna into bringing back summer while Hans stays behind to hold down the fort. Her horse bucks her off and goes back to the town square, leading Hans to gather a posse to bring back the queen themselves.
After Anna fails to bring Elsa, freezing her heart in the process, Hans and his group fight off Marshmallow and lock Elsa in the dungeons. Kristoff and Sven bring back a dying Anna, and the other nobles leave the two alone. Before he kisses her, he reveals that he had no intentions of saving Anna and that he wanted to rule Arendelle, letting Anna freeze as he intends on killing Elsa, telling everyone that she died in his arms as they say their wedding vows.
Elsa, Anna, Hans, Kristoff and Sven fight against the blizzard on the fjord, as Anna is left with two choices: go to Kristoff and unfreeze her heart or stop Hans and save Elsa. She chooses to save Elsa, freezing into solid ice. Elsa weeps, her arms over what was left of her sister, only for Anna to return to normal, her actions serving as the act of true love needed to unfreeze her heart. Realizing this, Elsa is able to unfreeze Arendelle and bring back summer, finally gaining control of her magic.
The relationship between the two differs between writers and artists, but the two most common interpretations either leaves them antagonistic towards each other (as they are in the movie) or make it to where they actually are a couple, Anna never meeting Kristoff. This is because their relationship in the film, though flimsy, was convincing enough that no one, not even the audience, was able to guess Hans' real intentions until he revealed it. Some shippers also claim that the trolls put Hans under a spell, and forced him to become evil, as in their song 'Fixer-Upper' they say they'll get the fiancé (Hans) out of the way.
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