Me, a foolish king who caused the fall of the country???

Emperor Xiao Heng of the Yan Dynasty, a brilliant military leader who expanded the empire to its greatest extent, dies after his fourth northern expedition, leaving behind a weak and scholarly younger brother, Prince Jin, as his successor. A century later, the Yan Dynasty is in ruins. The current emperor, Xiao Huan, is a decadent ruler controlled by the corrupt eunuch An Youliang and besieged by rebel forces. As the capital falls and rebels breach the palace, Xiao Huan commits suicide by throwing himself into the Nine-Curve Pool. In that moment, the soul of the great Emperor Xiao Heng reincarnates into the body of the fallen emperor. Waking up amidst the chaos, Xiao Heng discovers he is dressed in women’s clothing, a humiliating remnant of his predecessor’s bizarre preferences. He swiftly kills several rebel soldiers who attempt to assault him, revealing his true martial prowess to his terrified eunuch, Li Jinxi. Realizing the empire is on the brink of collapse due to the incompetence of his descendants, Xiao Heng resolves to restore order and reclaim his throne.

Xiao Heng escapes through a secret water passage but is pursued by Duan Yunfeng, the heir to the King of the North and a formidable warrior known as the "Slayer of a Hundred." During the escape, Xiao Heng dives into the pool to evade capture, but Duan Yunfeng follows him. In the water, Xiao Heng overpowers Duan Yunfeng, dragging him to shore before collapsing from exhaustion. Duan Yunfeng, captivated by the mysterious figure’s beauty and interpreting the encounter as fate, rescues him and brings him to his military camp. Li Jinxi, desperate to protect the emperor’s life, deceives Duan Yunfeng by claiming Xiao Heng is Princess Zhaoyi, a royal relative. Duan Yunfeng, who has been pressured by his father and King Chu Li Jichang to marry Li Jichang’s daughter, refuses the arrangement, declaring he will only marry a princess. He becomes infatuated with the "princess," unaware she is the emperor.

The political landscape is fraught with tension. Li Jichang, the King of Chu, has seized control of the capital and executed several imperial princes to eliminate rivals, positioning himself as regent with ambitions to usurp the throne. He allies with the King of the North, Duan Yu, but their partnership is strained by differing goals. Li Jichang seeks power, while Duan Yu remains nominally loyal to the Yan dynasty. Xiao Heng, observing these dynamics, recognizes that Li Jichang’s brutality has alienated potential allies and created an opportunity. He decides to use his disguise as Princess Zhaoyi to manipulate the factions against each other. When Li Jichang’s son, Li Min, demands the princess as a concubine, Xiao Heng challenges him to a competition. Duan Yunfeng easily defeats Li Min in horseback archery and hand-to-hand combat, further angering the Li family but solidifying his bond with the "princess."

Xiao Heng uncovers the extent of the corruption that plagued the late emperor’s reign, particularly the embezzlement by Eunuch An Youliang, who fled with the national treasury. He begins to formulate a plan to rebuild the empire’s finances and military strength. Meanwhile, Duan Yunfeng’s affection for the princess grows, and he formally proposes marriage, believing it will secure his political standing while satisfying his personal desires. Xiao Heng accepts the proposal strategically, knowing it will strengthen his alliance with the King of the North, a key military power. As the story progresses, Xiao Heng navigates the treacherous court politics, balancing his dual identity while preparing to confront Li Jichang and restore the Yan Dynasty’s glory. The reincarnated emperor must now use his wisdom and military expertise to turn the tide of history, all while maintaining the delicate charade that keeps him alive.