A Communist spy serving as an officer of the Japanese puppet regime joins hands with Russian and Korean spies to execute an assassination plot.
In the year 1941, Nazi Germany declares war against the Soviet Union. Given that Manchukuo's loyalties lie with Cheng Tian, the Russians are caught in a situation where they face threats on all sides. Their intelligence agency devises a long-term plan in secret. Communist spy Tang Fei (Liu Yunlong) receives a mission to infiltrate the enemy by pretending to be one of their own. At the Security Bureau, he crosses paths with Cai Meng (Han Chae Young), a woman determined to fight against the Japanese regime. They gain each other's trust as they try to outsmart the enemy within their own territory.
Can a hero with no combat abilities still save the empire? Wei Xiao Bao is the most unlikely hero as the sly but witty son of a prostitute during the early Qing Dynasty. As he makes his way from the brothel where he was born in Yangzhou to the capital city of Beijing, he encounters all kinds of trouble and mishaps.
When he is kidnapped and taken to the imperial palace, Xiao Bao impersonates a eunuch to survive. By accident, he meets the young Emperor Kang Xi and the two become unlikely friends.
Through sheer luck, cunning and other accidents, Xiao Bao is able to help Kang Xi protect his throne from dangerous challengers while surviving several kidnappings by cults and other dangerous groups. He also goes on to have seven wives, including the beautiful Shuang Er.
But can Xiao Bao ultimately choose between his conflicting loyalties to the emperor and the anti-Qing regime?
Sui Tang Yanyi begins in the 580s with the conquest of the Chen dynasty (557-589) by the Sui dynasty under Emperor Wen, and concludes with the return of the Tang dynasty's Emperor Xuanzong to the capital Chang'an in 758 near the end of the An Lushan Rebellion (755-763).
The plot is made up of three main story lines.
The first, with Emperor Yang of Sui and his concubine Zhu Gui'er (朱貴兒) as the central characters, covers the events in the political arena and inner palace in the final years of the Sui dynasty.
The second story line narrates a turbulent period known as the transition from Sui to Tang, when heroes such as Qin Shubao,Shan Xiongxin (單雄信), Cheng Yaojin (程咬金) and Xu Maogong rise up to overthrow the Sui dynasty, followed by stories of how Li Shimin (the future Emperor Taizong of Tang) defeated his rivals and eventually solidified the Tang dynasty's sovereignty over China.
The last story line tells of the romance between Emperor Xuanzong of Tang and Consort Yang, and the events of the An Lushan Rebellion.