Set in the Joseon Dynasty, at that time, twins were considered an omninous sign for the royals. As a result, when the crown princess gives birth to twins, an order is sent to kill the daughter among twins. To save that daugther's life, crown princess secretly sends someone and moves her out of the palace. A few years later, the twin daughter Da Mi returns to the palace to work as a maid. When the male twin, Lee Hwi, loses his life through a case of mistaken identity. Their mother persuades Da mi to take Lee Hwi's place. From then, she distances herself from everybody while living in the lonely palace and hiding her secret. However, Lee Hwi starts developing feelings for Jung Ji Woon, her original first love and later teacher who comes from a noble family. However, as she needs to live her life as a king, Lee Hwi, she cannot confess her feeling to Ji Woon.
Episode 1
Episode 1
Oct 11, 2021
Years after the crown princess delivers forbidden twins, Yi Hwi meets a court maid who looks exactly like him, to his amazement and his mother’s horror.
Episode 2
Episode 2
Oct 12, 2021
Dam-i tearfully bears the weight of the crown in guise of her brother. Jung Ji-un races against time to find a herbal remedy for a peeved patient.
Episode 3
Episode 3
Oct 18, 2021
Hwi spares Ji-un his life thinking they won't ever cross paths again. Later, she's startled to see him lurking inside the palace walls.
Episode 4
Episode 4
Oct 19, 2021
Ji-un proves to be a formidable opponent for Hwi, who's determined to make her newest royal tutor resign. Yi Hyun takes Hwi out on the town.
Episode 5
Episode 5
Oct 25, 2021
Ji-un's good-hearted attempt to make his pupil warm up to people in the palace goes awry. Prince Changun tests Hwi with an intoxicating surprise.
Episode 6
Episode 6
Oct 26, 2021
A familiar book on the crown prince's desk baffles Ji-un. Running out of time and the means to save his friends, he asks Hwi for help.
Episode 7
Episode 7
Nov 1, 2021
Hwi earns a chance to gain the king's trust during the Ming envoys' visit, but an ill-tempered guest tests the limits of her patience.
Episode 8
Episode 8
Nov 2, 2021
Ji-un comforts a tearful Hwi in his arms. Hyun and Ji-un team up to figure out the envoy's secret after a suspicious man visits his quarters.
Episode 9
Episode 9
Nov 8, 2021
The queen dowager tells the crown prince to wed. As Ji-un recalls previous night's events, he realizes the reason behind his rollercoaster of emotions.
Episode 10
Episode 10
Nov 9, 2021
After a joyous day together, Hwi gives Ji-un her answer. Shin So-eun and No Ha-gyeong visit the palace as candidates to become the next crown princess.
Episode 11
Episode 11
Nov 15, 2021
Hyun visits Ji-un at his new clinic. A furious Hwi holds Prince Changun accountable for his wrongdoing, and faces staggering backlash as a result.
Episode 12
Episode 12
Nov 16, 2021
The king is asked to answer to overwhelming appeals for the crown prince's removal. Reentering the palace, Ji-un promises to protect Hwi no matter what.
Episode 13
Episode 13
Nov 22, 2021
Hwi carefully reveals her secret to Ji-un. Lord Sangheon unleashes his royal ambitions and makes way for the future king.
Episode 14
Episode 14
Nov 23, 2021
Hwi and Ha-gyeong spend their first night together. Reinstated into a palace operating around Lord Sangheon, Ji-un lies low to serve the wounded king.
Episode 15
Episode 15
Nov 29, 2021
Moving in silence, Hwi strategizes retaliation against her grandfather. Kim Ga-on reappears in front of the king with a startling confession.
Episode 16
Episode 16
Nov 30, 2021
Yoon Hyeong-seol sets out to find the damning ledger and keep his promise to the king. Prince Wonsan puts two and two together about Hwi's identity.
Episode 17
Episode 17
Dec 6, 2021
Rumors about Hwi and Ji-un's close relationship circulate amongst the palace staff. To protect his son, Jung Seok-jo takes matters into his own hands.
Episode 18
Episode 18
Dec 7, 2021
Hyun and Lord Sangheon learn of Prince Wonsan's secret ploy to dethrone the king. Hwi prepares to take down her grandfather — alone.
Episode 19
Episode 19
Dec 13, 2021
Prince Wonsan ruthlessly proves his ambitions — and worthiness — for kingship to Lord Sangheon. Hwi prepares to abdicate the throne.
Episode 20
Episode 20
Dec 14, 2021
Returning to the palace with a vengeance and an army, Lord Sangheon and Prince Wonsan spare no one in their bloody path to the crown.