The mystery thriller revolves around a murder case set in Hansung, the capital of Korea during the latter years of the Joseon dynasty when the nation was experiencing a rapid influx of western influences.

Featuring a band of newcomers in the leading roles, Conspiracy in the Court entails a story of four young visionary idealists and King Jeongjo, Joseon's popular 22nd monarch who fought for commoners' rights and bureaucratic reformation.

Meanwhile, leading merchant Yang Man-oh (Lee Chun-hee) expands his power and influence by accusing his rival Hong of illegal doings to the police bureau.

It was also a period when the 400-year Joseon Dynasty was gradually losing ground, unable to respond to external and internal changes in the wake of the Japanese invasion of the 16th century and the Manchu War, resulting in clashes between the king, who dreamed of restoring his authority through powerful reforms aimed at improving the lives of the people at the grassroots level, and conservative political forces, which felt threatened by the self-justified royal authority.

[5] As this politically charged drama began airing during the peak of Korea's 2007 presidential campaign, viewers compared the ideal leadership model of King Jeongjo to current affairs.