Tang Yixuan, a top student in modern science and technology, accidentally traveled through time and became the legitimate daughter of the Tang family who was framed by Yongning Hou and her family was exiled to the north. Her brother, who was the county magistrate, died tragically at the hands of barbarians. In a desperate situation, she disguised herself as a man and took over the dilapidated Qingchuan County. Faced with the risk that her identity would be revealed, she would implicate the nine tribes. She made use of modern knowledge to build cement and build city walls, make penicillin to treat soldiers, and develop repeating crossbows, explosives and cannons to fight against the barbarians. He fought all the way from the border town to King Qin in the capital, and exposed the evidence of Marquis Yongning's collusion with the enemy and treason. After the Qing emperor sided with him, he was granted the title of Marquis of Beiliang. But Duke Zhen's cavalry has already moved south, and a more cruel game of power has just begun.
