The hero, Prince Siegfried, is out riding one day with his friends when he sees a swan with a crown on its head swimming on a lake. One of his friends, Adolph, tries to shoot the swan, but just before his arrow flies, Adolph is transformed into a statue. Siegfried's other friend Benno accuses the swan of practicing witchcraft, neither of them pondering the presence of an owl just behind them. Siegfried is unable to stop thinking about the swan, and decides to follow it as it swims away from its spot on the lake. Siegfried soon finds himself at a castle. Siegfried watches in surprise as the swan transforms into a beautiful girl. He approaches her - at first she is frightened for him and tries to get him to leave, but at his persistence she starts to tell him her story. Her name is Princess Odette, and three years prior she was kidnapped by the evil sorcererRothbart who wanted her hand in marriage. He keeps her a swan by day so that no one will fall in love with her, as the only way Rothbart's power can be defeated is when a man loves her with all his heart and soul. Siegfried explains that he already felt something for her the moment he saw her eyes, and asks her to go to his birthday ball the next night, where he will choose her as his bride. Although at first she refuses, Siegfried is intent and won't take no for an answer, convinces her and when she returns to her room she daydreams of him. The entire story is being seen through the eyes of Hans and Margarita, two squirrels who are watching them. Enter Rothbart. His daughter Odille tells him about Siegfried, and Rothbart goes to Odette to tell her to forget about the prince and consider marrying him. She rejects. Turns out she's been in love with Siegfried for the past three years. Rothbart is not going to let Odette go to the ball, so he bars the door and lifts the drawbridge. He and his daughter Odille then plot to get Odette to forget Siegfried by getting him to fall in love with someone else—Odille. Odille, transformed in the guise of Odette, goes to the ball and wows Siegfried with her dancing. Siegfried does feel that there's something wrong but can't quite put his finger on what it is. Meanwhile, Odette manages to escape from Rothbart's castle with the help of Hans and Margarita, the squirrels, and runs to Siegfried's castle. But just as Odette is about to storm into the ballroom, Rothbart grabs her, holds her mouth shut and brings her closer where she is able to watch but not make a sound. Thus she watches in horror as Siegfried pledges his love to Odille and announces her as his wife-to-be. Overcome with sorrow, Odette faints into Rothbart's arms. Rothbart's laughter gets Siegfried's attention and the prince quickly realises his mistake. Odille reveals her true form and the three of them transform into their winged shapes and fly back to the castle. Siegfried follows on horseback, where the final showdown between the two men takes place. Hans goes to help the Prince but Rothbart transforms him into a dead frog. After a long fight with Rothbart, the evil sorcerer has Siegfried cornered and held at sword-point. To save his life, Odette promises to Rothbart that she will love and marry him, but Siegfried, unable to bear the thought of Odette being a prisoner to Rothbart her entire life, pushes the sword into his own heart and causes a flash of light which destroys both Rothbart and Odille. Rothbart's castle collapses. Adolph transforms back into a human and Hans and Margarita are reunited. Odette and Siegfried, who ended up completely unscathed due to his sacrifice of true love, reunite and run into each other's arms as the sun rises on the ruins of Rothbart's castle.
