Modern person Su Jinhe time-traveled to the Hongwu era of the Ming Dynasty, becoming the small county magistrate of Fengyang County. At first he only wanted to keep a low profile to save his life and avoid court turmoil; but seeing the suffering of the common people, he resolved to serve a term in office and bring welfare to the locality. Relying on modern wisdom, he repaired water conservancy, ran industries, farmed and engaged in construction, making the poor county governed more and more prosperously; and relying on modern thought, he helped Zhu family's three generations of descendants, stepped forward bravely at the time of national crisis, and stepped by step became a pillar official supporting the Great Ming from a small county magistrate.