Set during the reign of King Sukjong in the Joseon dynasty, the series is based on the historical character Consort Suk. The story focuses on Dong Yi, a slave maid working in the Bureau of Music. Her warm personality, sincerity and exceptionally keen mind help her in solving difficult court intrigues and allows her to rise in the ranks, first as a Lady of the Court then a Concubine, despite being Lowborn. While solving a case, she meets the King who introduces himself as a Court Judge. He enjoys her treating him as a real court judge and he falls in love with her. She also gains the favor of Queen Inhyeon and meets Jang Hee Bin, another concubine who is first an ally but later a bitter enemy.