A famous general of the Northern Qi Dynasty, the King of Lanling, Gao Changgong, showed his skills in the Battle of Mangshan and repelled the Northern Zhou invaders, but when he returned to the court, he faced a more treacherous opponent–Quanchen and Shikai. Gao Changgong, his eldest brother Gao Xiaoyu, and general Duan Shao formed a team of justice to defend His Majesty, and fought round after round with He Shikai and his subordinates. At this moment, the folk hero Mulan suddenly broke into Gao Changgong's life. The cheerful and straightforward Mulan strikes Gao Changgong's heart, but there is an even more amazing secret hidden by Mulan......