Love is putting someone else's needs before yours.
Olaf is a major character in Frozen and the main protagonist of Olaf's Frozen Adventure. He is a hilarious snowman who guides Anna and Kristoff on their quest and an outcast from Queen Elsa's kingdom. His dream is to experience summer, which he eventually gets with the help of Elsa's magic.
He is voiced by Josh Gad, who also played Louis in Ice Age: Continental Drift, Ludlow Lamonsoff in Pixels: The Movie, and Chuck in The Angry Birds Movie.
Olaf and Sven star in the animated short used as the teaser trailer for the film. It begins with Olaf wandering around the snowy landscapes of the forest when he comes across a flower. Intrigued by its beauty, Olaf takes a whiff which causes him to sneeze, his carrot nose flying off into the center of an icy lake, where it's spotted by Sven, who's on the other side of the lake. The sight of the carrot was enough to get Sven extremely excited and head onto the slippery platform to fetch it, having Olaf believes he's trying to eat it. A race for the carrot then ensues, and the duo finally reach it, but Olaf accidentally flings it back onto the snowy land. Sven's able to escape the lake and retrieve the carrot before Olaf, much to the snowman's sadness. However, Sven returns and places the carrot onto Olaf's face, revealing he was merely trying to help get it back. Overjoyed, Olaf thanks the reindeer, the two forming a new friendship just before Sven's shedding causes Olaf to sneeze once again, though it's his head that goes flying off as opposed to the carrot.
When Anna and Elsa were children, Elsa would use her snow magic to play with Anna. A favorite pastime activity for the two sisters was building snowmen. On one such occasion, Elsa helped Anna build their own snowman they named Olaf to play with. Many years later, Elsa would exile herself from Arendelle after her magic was discovered and deemed dangerous. In the midst of embracing her abilities at her new ice castle home, Elsa recreates Olaf, but because of her magic, he is enchanted and given life. Olaf then wanders around the mountains alone and blissfully lost, until he bumps into Anna, Kristoff and Sven the reindeer, who seek to bring Elsa back to Arendelle so that she can bring back summer after she accidentally caused an eternal winter. Anna soon recognizes Olaf and quickly assumes it was Elsa who built him, to which he confirms. Kristoff then tells Olaf of their mission to bring back summer after Olaf constantly asked what their intentions on finding Elsa were. Extremely giddy with the idea of summer and its warmth, Olaf decides to happily guide the group to Elsa's castle, though Anna refrains from telling him about the dangers of summer for a snowman, leaving Olaf comically in the dark.
After a short journey, Olaf and the others find Elsa's ice castle, but the Snow Queen isn't too thrilled about the idea of returning to Arendelle, telling Anna to leave and enjoy her life where she belongs. Just then, Olaf arrives, overjoyed to see Elsa again. His presence proves there's love and beauty in her powers, as well as reminds her of the joyful moments she spent with Anna. However, their childhood memories also remind Elsa of the haunting night she nearly killed her sister, prompting her to leave the scene, asking Anna to leave once again. Anna refuses to leave without her sister, but the stubbornness only makes Elsa uncomfortable, causing her to lose control over her powers once again and accidentally freeze Anna's heart. She then orders them to leave once more, and once again, Anna refuses. In order to keep them away, Elsa creates a personal bodyguard named Marshmallow, a giant snowman. Olaf is thrilled to see another enchanted snowman, but is immediately kicked out along with Anna and Kristoff. After Anna tries his patience, Marshmallow chases after the group. Olaf tries to stop him, but is easily no match for the beast and is thrown over a cliff, which Anna and Kristoff fall over, as well, though they all survive. Once they recover their energy, Kristoff notices Anna'a hair turning white, rather alarmingly. To help, he takes the gang to a valley filled with mystical trolls. The king of the trolls, Pabbie, informs Anna that if she doesn't perform an act of true love, she'll freeze to death. The friends immediately rush back to Arendelle, believing a kiss from Hans, a prince Anna's engaged to, will break the curse.
Along the way, Olaf is accidentally separated from the group, and informs them that he'll meet with them at the castle. When he arrives, he finds Anna in the parlor, on the ground and quickly dying. She tells him Hans betrayed her, and Olaf doesn't hesitate to start a fire to keep the princess warm. Fearing he'll melt, Anna tells Olaf to leave, but not wanting to abandon his friend, the snowman stays by her side, nearly melting during this time. Olaf then asks what happened with the true love's kiss from Hans, to which Anna reveals his treachery, telling Olaf she doesn't even know what love is anymore. Olaf replies by telling Anna love is putting someone else before yourself, using Kristoff as an example, thus revealing his true feelings to Anna, much to the princess' surprise. Suddenly, the parlor's window bursts open due to the strong winter winds, and Olaf rushes to close it. Before he does, he notices Kristoff and Sven rushing back to the castle. Knowing Kristoff is truly the one that loves Anna, the two try to head out to meet him. Olaf then aids the dying princess out of the castle and into the fjords.
However, the powerful storm blows Olaf away, and once he reunites with everyone, he finds Elsa mourning for Anna, who unfortunately froze to death sacrificing her life to save Elsa from Hans. Fortunately, that was an act of true love, and the ice is thawed, restoring Anna's life, as well as saving the entire kingdom, bringing back summer. Overjoyed, Olaf smiles with glee, but quickly melts due to the summer heat. Elsa restores him and gives him a small little cloud to hover over his body and keep him completely cool, finally allowing the snowman to live his dream of experiencing summer and all its wonders. During the kingdom celebration, Olaf is seen throughout the village enjoying the sights and sounds of the warm season, taking a whiff of some flowers. The pollen causes him to sneeze, however, and his carrot nose lands directly into Sven's mouth. The reindeer doesn't hesitate to suck it up, saddening the snowman. However, this was only a playful trick, and Sven immediately places the carrot back onto Olaf's face, where it belongs, prompting the overjoyed snowman to hug his friend affectionately.
Olaf is last seen in the castle courtyard, enjoying the newly made ice skating rink created by Elsa for the kingdom's enjoyment.
Olaf is voiced by The Book of Mormon star Josh Gad, who would later play Ludlow Lamonsoff in Pixels.