In a sudden twist of fate, Qin Mu transmigrated and became the Crown Prince of the Great Qin Dynasty. He started with a daily login system, and ten years later, he successfully reached the supreme realm of a terrestrial immortal, becoming invincible. Just then, the previous emperor passed away, and Qin Mu successfully ascended the throne, adopting the reign title Yongyuan. Because he was already invincible, and the system's various rewards included generals and capable ministers secretly helping him govern the land, Qin Mu immediately began a life of leisure, indulging in debauchery and revelry. However, unexpectedly, the entire court criticized him for being obsessed with beauty and incompetent, while Xu Longhu, the heir of Xu Xiao, the Prince of Zhenbei, was filled with ambition and plotted to replace Qin Mu! To this end, he devised a four-step plan: First, to win over officials outside the three northern states and form the Northern Frontier Party; second, to offer his beloved concubine to Qin Mu to steal intelligence; third, to consolidate the military power of Zhenbei and place his family members in the army; and fourth, to bribe the commander of the Imperial Guard of the Great Qin capital! If the four-step plan succeeds, he can march straight in, replace Qin Mu, and become the Emperor of Qin! Little did he know, Xu Longxiang's every move was under Qin Mu's control. To him, it was nothing more than watching a clown's performance. This was a perfect opportunity to see clearly who the true loyalists of Qin were and who the traitors were! On the day a million rebel troops besieged the city, Lu Bu, Xu Da, Huo Qubing, Han Xin, and many other historical generals appeared, instantly surrounding the million-strong army. And Qin Mu, with a flick of his finger, wiped out the five Celestial Mirror advisors that Xu Longxiang relied on! Xu Longxiang's eyes widened, utterly devastated: "Impossible! This is impossible!" Qin Mu smiled faintly: "I am invincible, that's why I lie low. If I were to make a move, the heavens would fall."

The story takes place in the fictional Chinese kingdom of Caiyun. According to legend, a young man, aided by the power of the Eight Immortals, founded Caiyun. Consequently, Caiyun's territory was divided into eight provinces: Hongzhou, Huangzhou, Bizhou, Lanzhou, Zizhou, Heizhou, Baizhou, and Chazhou. Approximately 600 years ago, the king of the time ordered the nobles of each province to adopt one of these eight colors as their surnames (for example, the Marquis of Lanzhou became Lan, the Marquis of Hongzhou became Hong, and so on). Commoners were prohibited from sharing surnames with these eight marquises. Consequently, those bearing these eight colors were considered the most aristocratic of the nobles. Furthermore, because the Marquis of Zizhou, where the capital was located, also served as king, the Zi family became the royal family's surname. Despite being born into the prestigious Hong family, Hong Xiuli lived in poverty. She had to work extensively to support her family. Having experienced the turmoil of the throne struggle as a child, she deeply understood the suffering of the people. From a young age, she diligently studied, hoping to pass the imperial examination, become an official, assist the king, and build a prosperous and peaceful nation. However, as a woman, she cannot take the imperial examination. One day, Xiu Li accepts a high-paying commission from Grand Tutor Xiao and enters the harem as a noble concubine to teach and assist the incompetent emperor. This opportunity leads Xiu Li to a career as an official, and she encounters a variety of people.