Swan Lake

The sorcerer Von Rothbart turns Princess Odette into a swan, then takes human form as adviser to a Queen. She tells her son, Prince Siegfried, that he must choose a bride at a ball the next evening. He slips away to a moonlit lake, where a swan lands and becomes Odette. Only a vow of undying love from one who has never loved before can free her. Siegfried swears it, and Von Rothbart sets out to make him break his word.