Elsa flees Arendelle right after the coronation, due to her powers becoming out of control. Anna goes after her and finds her in a palace of ice, surrounded by soldiers. Elsa shields Anna from the soldiers' blasts by creating an ice wall. A grenade is lobbed over the wall and collapses the ground beneath Elsa's feet. Although Anna dives to catch her, she is too late and Elsa plunges into the dark, foggy valley below. Anna is distraught but knows that she must go back to defend Arendelle. Anna and her soldiers capture one soldier. Before he commits suicide, he only tells them that the group is called Hydra, and that when you cut off one head two more shall take its place. With Elsa presumed dead, Anna is crowned Queen of Arendelle and reigns in peace for ten years. Then, whispers of a super soldier who fights with ice reach Arendelle. Anna knows that this warrior must be stopped. She names the Duke of Weaselton as her regent and teams up with Kristoff, the Falcon on Ice, to meet the soldier before he can cross into Arendelle. Using intelligence reports, Anna and the Falcon realize that the soldier is probably camped out at the ice castle. They go and confront the mysterious soldier. During the battle Elsa's mask falls off. Anna can't believe it's her, and asks, "Elsa?" to which Elsa responds, "Who the hell is Elsa?" The Falcon takes the opportunity of Elsa's confusion and takes a shot at Elsa, spraying snow everywhere. When the snow settles, Elsa is gone. Special Arendellian forces arrive, but instead of helping Anna and the Falcon they arrest them, by order of the Duke. Anna realizes that she has been betrayed and that the Duke, and these particular soldiers, were with HYDRA all along. However, the vast majority of her people and soldiers have no idea of the Duke's treachery. She and the Falcon are put in the dungeon. Olaf breaks them out by picking the locks with his nose and tells them the plan that he overheard: three colossal ships full of soldiers are sailing from the Southern Isles. The Winter Soldier is going to freeze the Arendellian navy, leaving Arendelle defenseless. Anna and the Falcon rally her soldiers and the townspeople against the Duke, but seeded HYDRA operatives try to kill her. Realizing that their beloved queen is in danger, Anna's people begin to fight against the HYDRA operatives in the town and in the castle. Anna and the Falcon slip away to confront Elsa. Elsa blasts the Falcon with ice. Anna fights with Elsa. As Elsa has her pinned down with ice, Anna asks her, "Do you want to build a snowman?" This triggers Elsa's memory and she unfreezes Anna, the Falcon, and the ships. The Arendellian navy sails out to meet the ships coming from the Southern Isles and defeats them. The Duke and his HYDRA agents are captured. Elsa formally hands over the crown to Anna. Although Anna begs her to stay, Elsa decides to retreat to her ice palace, where she can heal and figure out how to use her powers for good.