The state of Wei has been at war with the northern barbarian Rouran for years, and Lao Shanyu wants to retreat. However, his son Maodun (played by Hu Jun) is violent by nature and intends to annex the Central Plains. In order to defend against foreign enemies, the Wei State conscripted young men into the army to serve the country. Considering that her father Hua Hu is old and seriously ill, her daughter Hua Mulan (played by Zhao Wei) resolutely decides to disguise herself as a man and take her father's place...