In the modern age, Jang Bong-hwan is a chef who works for the country's top politicians at the Blue House. He has a free spirit, but he one day finds himself in the body of Queen Cheorin in the Joseon period.
Bong Hwan is a successful young chef, but he finds himself in trouble. After accidentally falling into a swimming pool while being chased by the police, he wakes up in the Joseon dynasty in a woman’s body. And the body he is trapped in belongs to the future queen of all people. Bong Hwan must find a way to go back.
Bong Hwan’s life as So Yong, the queen, begins in earnest. The rigidity of the palace wears Bong Hwan out, but he runs into the woman of his dreams. The problem is that she is Jo Hwa Jin, the woman King Cheoljong is in love with. Meanwhile, the Grand Queen Dowager and Kim Jwa Geun sense that something is off with So Yong.
So Yong escapes from danger with the help of her cousin, Byeong In. Cheoljong becomes aware of the Kim clan’s movements to protect So Yong and grows suspicious of her. Meanwhile, So Yong misses modern food and decides to make it herself in the royal kitchen. She decides that she must win over the Grand Queen Dowager’s heart with food.
So Yong gets furious as she realizes it is Cheoljong who is trying to kill her. Cheoljong also assumes So Yong is planning revenge over him as O Wol, the court maid of Hwa Jin, goes missing after that.
To save Hwa Jin, So Yong reveals the truth about the lake incident in front of everyone. Grand Queen Dowager gets angry at So Yong for ruining her plan in bringing down the Jo clan. Meanwhile, Cheoljong feels bad for So Yong as he realizes that she jumped into the lake by herself.
Cheoljong saves So Yong when she jumps into the water to go back to the present day. Cheoljong starts to see So Yong differently and tries to start fresh with her. Meanwhile, So Yong is hopeless as she fails to go back even when she drowns herself in the lake. She attempts every method to get in touch with the spirit that is in Bong Hwan’s body.
After inventing delivery system in Joseon dynasty, So Yong gains motivation in her new life. However, she suddenly travels back into the body of Bong Hwan in the present day and realizes that he is in a vegetative state. Meanwhile, as the spirit of Bong Hwan left the body of So Yong, she collapses and that leaves the Palace in an uproar.
When Bong Hwan wakes up in So Yong’s body again, he regains more memories of actual So Yong. He gets upset as he loses his true identity from the present day. Meanwhile, Hwa Jin feels insecure as Cheoljong visits So Yong in her family house. Hwa Jin quickly follows after him to stop Cheoljong from seeing So Yong.
So Yong wants to go back to the Palace, but Cheoljong suggests staying one more day as he is still looking for the secret ledger. Cheoljong goes out to the street in disguise, and So Yong accompanies him. Meanwhile, Queen Dowager braces herself to fight Grand Queen Dowager back after she gets insulted.
Cheoljong returns to the Palace without finding the ledger. He wonders who took it away before he did. Meanwhile, So Yong tries to become a perfect queen to satisfy the Grand Queen Dowager when she returns to the Palace. Also, she starts the investiture of the Royal Concubine to hunt down the Han family.
Cheoljong appears in So Yong’s dream and So Yong is confused about her feelings. She assumes it is a side effect from travelling back and forth in time. She decides to focus on the investiture of the Royal Concubine to retrieve her true identity. Meanwhile, Cheoljong prepares for the royal banquet, but someone tries to ruin it behind his back.
So Yong tracks down the man who looks exactly like Secretary Han and notices his shady move in the Royal Kitchen. As she knows how much effort Cheoljong has put into the banquet, she helps him by doing what she does best. Meanwhile, Kim Jwa Geun suddenly delivers a piece of news in front of everyone to threaten Cheoljong.
Cheoljong gets seriously injured from the explosion and become unconscious. Kim Jwa Geun threatens So Yong again to accept his suggestion, and So Yong jumps into the lake to regain more memories. Meanwhile, Kim Jwa Geun believes that So Yong is no longer on his side as he finds out that So Yong helped Cheoljong to save the banquet.
So Yong gets drunk and mistaken Cheoljong for Hong Yeon. So Yong starts avoiding Cheoljong when she finds out that they spent the night together. Cheoljong gets upset because So Yong treats him harshly. Meanwhile, someone comes to see Cheoljong and tells him that So Yong is in danger.
Everyone who lives in a palace has secrets. Bong Hwan is a chef working at the Blue House in the present day. He is so talented that he can figure out one’s health conditions and even get into their mind by just observing what they pick for their side dishes. He somehow gets trapped in the body of Kim So Yong, a queen in the Joseon dynasty, and meets King Cheoljong, the two-faced king full of secrets.
After Cheoljong shares about the future of Joseon he dreams of with So Yong, she decides to help Cheoljong to fulfill his dream by applying knowledge from the present day. Byeong In feels jealous as Cheoljong and So Yong become closer every day. Meanwhile, Hwa Jin decides to tell Cheoljong the truth about the well incident.
Everyone including Cheoljong in the palace is happy to hear about the Queen’s pregnancy. However, So Yong can’t believe that she is pregnant and is not happy about it. Cheoljong is suspicious about So Yong’s reaction and he tries to comfort her. Meanwhile, a fierce rumour also starts to spread with the news of the Queen’s pregnancy.
Cheoljong leaves the Palace to protect So Yong. So Yong worries about him as he disappears without any explanation. Meanwhile, the Grand Queen Dowager regains her regency as soon as Cheoljong leaves his spot, and she brings back Kim Jwa Geun to assist her. Byeong In tries to persuade So Yong to reconcile with the Kim clan, but she rejects his suggestion.
So Yong runs away from the Palace to look for Cheoljong, and Byeong In chases after her. Byeong In tries to kill So Yong on the edge of a cliff. Meanwhile, the Palace is busy with the preparation of the enthronement ceremony. However, someone goes around the streets and spreads the news that the King is still alive.
Cheoljong and So Yong plans to go back to the Palace in safety while Grand Queen Dowager and Kim Jwa Geun strictly restrict the entry. However, Bong Hwan’s soul suddenly leaves So Yong’s body when she is in danger. Will they be able to stop Kim Jwa Geun before the enthronement ceremony?