Hong Joo Won (Seo Kang Joon) is at a total loss for words as Hawi (Lee Yeon Hee) finally confesses that she has been attired as man. He speaks from his heart to his best friend Kang In Woo (Han Joo Wan) and vents his anger about the woman who has deceived by not telling the truth.
After Hwai left with Joo Won to have an honest talk, In Woo finds a man intruder in his friend's house. In Woo took of his mask is totally surprised at his father's man.
Kim Gae Shi (Kim Yeo Jin) investigated Doha, a faithful servant to Kang Joo Sun (Jo Sung Ha), in secret advises Gwanghae (Cha Seung Won) to keep eyes on Joo Sun saying sometimes an enemy lies hidden in the likeness of a friend.
Joo Sun invited Yi Icheom (Jung Woong In) to his house hosts King's right-hand man with devotion and care. Icheom is dubious about the unexpectedly profuse hospitality.
In Woo gets to know his father's man stole into the friend's house because of Hawgidogam.
"I am not interested in having power you said, but I will build up my own power if you try to break my best friend." he warns him.
He meets his mother on the way out and she eyes him with contempt because he is the child of a low-class concubine. He clenches his teeth.
Princess Jeongmyeong makes a polite apology for not telling the truth demanding herself like a man to put Joo Won's mind at ease, but he seems to be a little restless.
In a room at the same tavern, Heo Gyun (Ahn Nae Sang) drinks with Doha to reveal the force behind him. Doha walks out on Joo Won and Hawi. He harbors suspicion about the young worker in a sulfur mine in Japan standing next Hong.
On their way home, Hwai asks him to keep the promise for her to work in Hawgidogam. He refuses resolutely at first, but staggers at her words that she knows a method of smelting sulfur with steam.
Crown prince attends at Manggweolrye (A ritual of celebrating the birth of Emperor Ming) on the King's behalf who caused a stomachache all of a sudden. But Gwanghae is idly leafing through a book drinking tea.
Senior statesmen complain about the King's inappropriate behavior, but Gwanghae even speaks with finality that he will not dispatch soldiers to Ming to seek utilitarianism. Joo Sun urges the King to meet the needs of Ming saying the nation of poor power can't stand alone without Ming's help.
"I have been waiting for someone saying like that. Today the door of Hawgidogam will open until has been shut tight. Let's go together." Gwanghae says decisively.
Jeongmyeong's face clouds over when she hears the news that the King is coming. The visitor watches the stepbrother from a distance with eyes brimming with tears.
Joo Sun is totally disconcerted by the tremendous amount of sulfur will be supplied from Japan and he recalls Joo Won's dripping gown in the returned ship from Japan. Gwanghae shows Choi Moo Sun's stolen book about manufacturing methods of gunpowder which Heo Gyun had regained strenuously insisting that Joseon has to build up its power to stand on its own feet without Ming's help. The senior statesmen so surprised they just stand there with his mouth gaping.
Gwanghae sincerely expresses his thanks to Joo Won about the new start. The young retainer appears a little confused at the unfamiliar attitude. After the King left, he is lost in deep thought.
Meanwhile Joo Win confirms success of Hawi's steam refining method.
Hawi caught by guards of the organization because she doesn't have pass and doesn't know secret code bumps into Gwanghae about to leave. She stares at the King and he looks closely at the young man in wonder.