Lin Xuan, a modern-day person, suddenly time-travels to the ancient Dazhou Dynasty. Relying on modern technology, he becomes the richest man in Exian County and transforms it into a town brimming with modern vibes. Due to Exian's unusual developments, the Empress Dowager suspects Lin Xuan of trading with foreign states. She disguises herself as an imperial inspector to investigate him, only to encounter a Xiongnu attack on Exian. As the Empress's identity is about to be exposed and the Xiongnu are on the verge of breaching Exian City, a life-or-death crisis unfolds.