Once upon a time, in a faraway country there lived a young girl called Yoona. She lived in a big mansion with her stepmother, Sunny and her two stepsisters, Yuri and Tiffany. Yoona was kind and lovely while her stepsisters were selfish and ugly. Her stepmother did not like Yoona very much. She made her do all the work and let her sleep in a room near the kitchen. But Yoona always looked on the sunny side of life. She did her work cheerfully and made friend with other people. Now, the king of country, King Lee Teuk hoping his son, Prince Siwon would marry and settle down. But how could he get his son to meet right girl? Then he had a very wonderful idea he could have a ball in honor of his son. "And if all eligible maidens in my kingdom just happened to be there."