Heo Gyun and Eun-sil, who realized their feelings for each other too late, spend happy times together. And finally, Heo Gyun, who revealed all of Lee Hyuk's evil deeds, accepts his fate of having to return to Joseon.

Heo Gyun, who has regained his memory, knows that he must return to Joseon to save his friends, but he cannot leave Eun-sil behind, and is conflicted. Meanwhile, Eun-sil, who has been appraised by Domun Daejak, learns of Heo Gyun's true identity.

The misunderstanding between Heo Gyun and Eunsil grows bigger and bigger. Heo Gyun struggles to protect Heo's Diner. The memories that are tangled with the reason why he came here begin to come to mind.

Heo Gyun, offered the opportunity to work at Lee Hyuk's restaurant, cannot easily refuse due to Eunsil's mother's hospital bills. Lee Hyuk puts his plan into action to bring down Heo's diner..

The restaurant becomes more and more famous through word of mouth due to Heo Gyun's extraordinary cooking skills, and Heo Gyun and Eun-sil gradually become closer. Lee Hyuk, who runs the restaurant across the street, who has been coveting the restaurant, becomes increasingly impatient...

Heo Gyun, who is a genius even in cooking, seems to agree to Eun-sil's suggestion to open a restaurant together, but he is not sure if he will accept her offer... In the meantime, Heo Gyun is confused when he meets Mi-sol and an old woman who look just like his acquaintances in Joseon.

Heo Gyun saved Eun-sil's mother's life, but his identity is unknown and he is suspected by the police... Eun-sil, who can't cook, is in danger of having to close down her restaurant...

Believing that 21st-century Seoul, where there is no class discrimination, is the authentic 'Yuldo-guk' of his dreams, Heo Gyun begins his chaotic adaptation at the grumpy Eunsil's small diner.

Joseon's genius, Heo Gyun, gets entangled in a conspiracy while living in exile and is pursued by assassins. Just as he faces certain death, he finds himself in the heart of 21st-century Seoul.