In 450 A.D. in China, the dynasty was under constant threat from the ruthless Rouran tribe. With such a major security threat at hand, the Chinese army conducted a nationwide draft. A retired soldier named Hua Hu insisted on enlisting again to serve his country. Mulan (Vicki ZHAO Wei), his young daughter, was intelligent and skilled in martial arts. But as a girl, she couldn't be enlisted. Unable to bear the thought of her father suffering, Mulan got her father drunk, dressed as a boy, and entered the army to take his father's place. Through the harsh military training, Mulan proved to be courageous and unstoppable, and always helped others to fend off the army bully. She gained the attention of the Wentai (CHEN Kun), the battalion's Vice-commander. They soon developed a mutual admiration. However, Mulan was in constant danger of revealing her gender. When Wentai ran into her bathing by accident, Mulan was fortunate enough to escape without exposing her identity, but Wentai was determined to uncover the woman hiding among the troops. To make things worse, the army bully had lost a jade pendant and a strip-search was ordered. Terrified to reveal herself and tarnish her father's reputation, Mulan admitted to the theft and was sentenced to death. In prison, she told Wentai the truth and he promised to keep this secret till the end. When the Rourans launched a surprise attack, Wentai released Mulan from jail to let her flee. But Mulan stayed for battle and decapitated the Rouran general. Her life was spared because of this merit, and even promoted to become Vice-commander. Together, Mulan and Wentai fought through various battles, and their friendship gradually turned into romance. However, the Rourans were getting stronger as their prince Mudan murdered his father and seized the throne. Facing an unprecedented scale of attack, Mulan was vastly outnumbered, and both her love and brevity were put to the ultimate test. Would she sacrifice true love for the peace of her nation?