Jewel in the Crown

The story begins in 1681, 7th year of King Sukjong. Dong Yi lives with her father and brother in a slave village. They are the members of Sword Fraternity, which is the organisation made up of the lowest class people. Then, a high ranking government officer from Southern Faction was assassinated. After that, Dong Yi finds the assassin ID and hand it to the police. But, it belongs to a corrupt policeman who worked for Oh Tae Seok. He is arrested, but gets killed in his prison cell. Dong Yi's father has the information, so Oh Tae Seok's masked man try to kill him but he gets saved by his friend, Cheon Soo. When they get home, Dong Yi is not there.

Oh Tae Seok wants to frame Sword Fraternity for the murders of Southern Faction and the police officer. Chief Seo asks his father to speak to the king about opening the investigation again. But, King Sukjong is at his father's grave. So, Chief Seo's father goes to visit him there. The Sword Fraternity realise that Oh Tae Seok is planning something. They rush to stop it, but all of them are dead. The corrupt police tries to frame them, but they manage to escape. Meanwhile, Dong Yi finds herself in a noble lady's house. Dong Yi prepares to do the greeting, but her father refuses to let her go. But Dong Yi sneaks away. She has to greet Oh Tae Seok. He then realises who she is and ask his men to kill her. But, Cheun Soo saves her. Then, a member of Sword Fraternity betrays them and leads to the arrest of Dong Yi's father and brother.

Dong Yi's father and brother are taken into custody. Dong Yi is taken to a fortune teller's place. He predicts she will be the leader of Sword Fraternity. Oh Tae Seok announces that Dong Yi's father and brother will be executed the next day. Some evidence has been found in the Sword Fraternity headquarters to prove that they are guilty. Cheun Soo and members of Sword Fraternity make plans to free Dong Yi's father and brother. Dong Yi sees a young aristocrat lady do the same hand signal that the dying official has showed at the riverside. The escape plan works, but they get chased and killed. Dong Yi hears that her father has escaped and runs to find her. But, she only sees corpses and the embroidered purse she has given to her father.

Chief Seo orders the city to be searched for members of Sword Fraternity. Dong Yi is still on the wanted list. So, when she takes her friend, Gae Doo La to the hospital, she is arrested by Chief Seo. Luckily, he lets her go and tells her about the hand signals. Dong Yi asks her brother's friend, Seol Hee to get her into the palace as a servant because she wants to find out what happened to her father. Meanwhile, a girl's body is found and Chief Seo confirms it although it is not her. Dong Yi enters the palace and starts working in the music department. She starts to play a sorrowful tune using a daegeum, which reminds her of her brother and father. Many years later and it's now the 19th year of King Sukjong and Dong Yi is now a young woman.

Six years have gone by and Dong Yi is now a young woman. Then, a meteorite is landed in the palace, a bad omen. Jang Ok Jeong's protesters blame this on her. Furthermore, the Western Faction is stronger than the Southern. Jang Ok Jeong is supported by Southern Faction, but the Western Faction is supported by the Queen Dowager and Oh Tae Seok. They do not like her and plan a 'bad omen'. Later at the banquet, the orchestra can't play in tune and says that it is a bad omen. Dong Yi tries to find the lady with the butterfly accessory. But, she is found loitering around and she is arrested and tied up in a barn with a dead man with the chimes earlier.

Dong Yi manages to escape before she is killed by the bad guy. She finds a policeman but when they go back to the barn, the body is gone. The capital is in turmoil because of the bad omen. The King is determined to find out who is responsible for the musical disaster. But the police and tribunal have come up with nothing. Dong Yi decides to do the investigating herself. She takes evidence dropped by the bad guy and then goes back to the barn, where the King turns up. Then, there's an argument outside the barn and the King bumps into Dong Yi when he hides. They escape together and as the collect more evidence, they get cornered by armed men.

The King keeps saying who he is. Luckily, Chief Seo and his men arrive and save the day. The Queen Dowager devastated to know that her plan has been foiled and the King's life is in danger. And he now knows that someone has changed the music chimes with rock salt. Jang Ok Jeong hands the ID of the corrupt policeman to the Queen Dowager. The Queen Dowager is furious and sees this as a threat. Oh Tae Seok's brother, Oh Tae Poong, who is a new director, comes to the music department and his son takes interest in Dong Yi. He wants her to be beaten up when she refuses him. Luckily, Dong Yi is called by Jang Ok Jeong, who wants to meet her.

Dong Yi wants to take a look at Jang Ok Jeong's personal hanbok accessory as a reward for helping to prove that she is not the cause of the bad omen. Dong Yi is sent to bring medicine into the palace by Jang Ok Jeong's mother. Dong Yi gets back to the palace late and can't sneak in and she is helped to get back into the palace by the King. Jang Ok Jeong refuses to drink the medicine. Then, the word spreads that poisonous herbs have been found in Queen Inhyeon's medicine. Dong Yi goes to pay her respect on the 6th anniversary of her father's and brother's death. On her way back, she gets arrested on suspicion of trying to poison the Queen.

The pharmacist who gave Dong Yi the herbs has been murdered. Police interviews Dong Yi, but she says that she gets the medicine for a musician and not Jang Ok Jeong. Chief Seo turns up and when he hears her name, he asks if she is Dong Yi that he knew. But, she says no. The ladies who investigate crimes that are committed by the women are very strict. And they have been ordered to investigate Dong Yi for buying the herbs and illegally bringing it into the palace. Torture tools are being prepared because Dong Yi still refuses to say who sent her to buy the herbs. Then, Jang Ok Jeong arrives just in time to confess that she is the one who ordered the herbs.

Jang Ok Jeong has voluntarily agrees to be investigated. The herbs are found in the Jang Ok Jeong's quarter and she is charged with trying to kill the Queen. But, Dong Yi convinces that Jang Ok Jeong is innocent because the herbs in question are different from the one that she has bought. Then, Oh Tae Seok tries to find a scapegoat to put the blame on and he picks Dong Yi. Meanwhile, Cheun Soo is alive and he gets a job at the city morgue. One night, Dong Yi sneaks into the morgue to check the pharmacist's body for evidence. She finds her evidence and as she sneaks out of the morgue, Chief Seo catches her. So, she tells him about the evidence. On her the way home, she is cornered by assassins but the King turns up.

Dong Yi is saved by the King's guard. She tells him that she has evidence to prove Jang Ok Jeong is innocent. The King and Chief Seo gather in the morgue to watch the procedure again. Unaware of the new development, Queen Dowager and the Investigation Bureau are happy on the downfall of Jang Ok Jeong. Jang Ok Jeong's brother, Jang Hee Jae who is a criminal, arrives from Qing. Then, because of her help, Dong Yi finally gets her reward. She is going to be promoted to court lady in the inner palace and will work in the Investigation Bureau.

The court lady investigators don't want to accept Dong Yi because of her low class origin. But, the Queen who is the head of the inner court refuses to change her decision. Dong Yi arrives at the bureau and gets her new uniform. But, other court ladies are angry with her because they have studied for 10 years to get where they are now and she gets in because of the recommendation from Jang Ok Jeong. Then, she finds out that the investigators are studying for their midterm tests. An evil Investigator Yoo doesn't want Dong Yi in her department. So she tells Dong Yi that she must take the test and not to worry about not knowing anything. But, she does not explain to Dong Yi that she will be expelled from the bureau if she fails the test.