Princess Anna is the younger sister of Queen Elsa, who possesses the power to create and manipulate ice and snow. However, Elsa's magic causes an endless winter to fall over the kingdom of Arendelle, forcing her to flee into isolation in fear of hurting others. Anna embarks on a journey to find and reason with her sister, encountering obstacles along the way such as giant snow monsters and treacherous weather conditions.
On her quest, Anna meets the rugged ice harvester Kristoff and his loyal reindeer companion, Sven. Though initially reluctant to help her, Kristoff agrees to assist her out of a sense of responsibility and eventually begins to develop feelings for her.
Anna and Kristoff must also contend with the scheming Prince Hans, who manipulates Anna into believing he loves her in an effort to seize the throne. However, Anna ultimately discovers Hans' true intentions and is saved by the love of her sister, Elsa. Elsa realizes that love is the key to controlling her powers and reconciles with Anna, lifting the curse of eternal winter and restoring peace to Arendelle.
Throughout the film, Anna also befriends the naive and whimsical snowman, Olaf, who dreams of experiencing summer. Olaf provides comic relief but also demonstrates loyalty and bravery in helping Anna and her companions on their journey. The film emphasizes the importance of sisterhood, self-acceptance, and the power of love to overcome challenges.