The drama starts with a young man (Jeon Nok-du), diving into the water, fishing for food with his spear. As he re-surface with his spear, a little girl (Aeng-du) cheers for him, on land calling him husband.
The camera gives us a glimpse of his masculine body as he returns to shore (and thank you, PD-nim! You know how to captures us viewer’s attention with those chocolate abs) and then pans out to show they are on an island.
As he and Aeng-du sits on the beach, cooking the fish and abalone, he explains to Aeng-du that there is something he must do away from the island therefore cannot marry her, resulting in Aeng-du grabbing his wrist, refusing. (Those red marks. Little girl sure has strength, I would hate to piss her off, lol). She states that he had promise her father he would marry her which he counter that he had no choice if he were to learn martial arts from him.
As her drunken father stumbles towards them, Aeng-du informed him that Nok-du refuse to marry her causing Nok-du to backtrack saying she is too young at the time. His master counter that he is the youngest male on the island hence they’re “soulmate”. (There is no way he is getting out of this marriage, huh? Can’t blame her for wanting him as her husband. Girl got taste, lol).
A woman runs up to them, informing Nok-du that something bad has happen at his house causing him to rush off. A group of assassin faces off with his father and injured brother. Nok-du flies into the yard, to face off with the assassin. He fights with the assassin, killing all except one. He slashes the assassin’s leg, holding the sword to their neck, demanding to know who they are.
The assassin pulls out a sword to commit suicide however Nok-du disarm it, still demanding to know who they are, why did they come. But before he could ask more question, his father grabs him to let the assassin go.
His father holds him back, asking him to stop asking further. He tells him that they must leave the island, claiming that the assassin was after him because he had committed a crime. Nok-du looks around at the dead assassin and his injured brother, knowing that it was further from the truth.
“I know it’s because of me. The reason why we’re hiding out on this island, the reason they’re running away again, and the reason his mother pass away like that,” he tells his father.
Nok-du runs to his brother to check on his wound which his master said is not serious, informing Nok-du that those were skilled assassin, wondering where they came from. Nok-du asks his master to take care of his father and brother so he can go after them.
His master advises him that finding one or two will not solve the case as they were willing to die, that he must seek out the leader. Nok-du nod as he goes after the escape assassin. His injured brother crawls over to pull down the assassin mask and is surprised to see that it’s a woman. (And I sure like what I am seeing as he runs across the beach, giving chase to the assassin. PD-nim definitely wants to make sure we get to see plenty of skin’s from Nok-du. I approve! I approve! Show us more, lol)
Elsewhere, a young woman (Dong Dong-joo) disguised as a man is rushing to follow the King’s procession taking place on the street. Hiding on the side of a house, Dong-joo pulls out her hidden bow to assemble and shoot her arrow directly at the King, hitting him on the side. The guards rush over to her, their swords at her neck. Unflinching, Dong-joo continue to look on at the King’s direction as a tear, that she succeeded, falls down her face.
But all the swords by her neck slowly vanishes showing us that it was all just her imagination. The assassin disguised as a man dress in red limp by her and just as she pulls out her bow to assemble, Nok-du accidentally bump into her, trying to give chase to the limping man, causing Dong-joo to drop her bow.
Just as Nok-du glimpse down at the bow, Dong-joo pushes him away and quickly grab it back causing Nok-du to lose sight. Nok-du sigh and runs off to continue his search as Dong-joo see that her chance to assassinate the king is lost. As she tries to find another place, the King’s procession comes to a halt as an elder man throws a rock at the King, hitting him on the head on behalf of his dead son and grandson, accusing the King of wasting money and taking innocents lives to build his palace.
The soldier arrests the elder man and as it turns out, the injured King is a fake. The real King (King Gwanghae) had disguised himself as a captain on horseback and assuming there is accomplice, order his minister (Minister Heo) beside him to search and arrest. Seeing the situation at hand, Dong-joo discard her boy and arrow trying to flee. Nok-du sees his assassin and give chase to the shed but before he can catch the assassin, the guards stop him. Struggling to be free, Nok-du tells the guard there is someone hiding in the shed.
The guard comes over to the shed to open the door only for a noblewoman to emerge out of there. As the woman walk away, Nok-du realize it’s the assassin in disguised as he notices her limping away and tries to break free from the guard. He chases after the assassin and pull the cloak off to see her face, surprise that it is a woman before the guards catches up to him and arrest him, as the assassin walk away.
The guards end up arresting Dong-joo as well, placing her in the same jail cell as Nok-du. Seeing him, she grab him by the collar, “I lost him because of you.” She blames him for bumping into her, making her lose her chance and vice versa. The two bickered pulling in the age rank which Dong-joo claim she is older until the guard shout for them to be quiet.
As the night falls and everyone has fallen asleep, Dong-joo sneakily kicked the loose bar she noticed earlier to slide through to make her escape. However, her shoulder gets stuck and an awake Nok-du wonder if she is an accomplice, telling her that if they’re innocent, they would be release tomorrow to and if caught escaping, she would be killed.
Dong-joo insult him when she questions if he is naïve or just stupid causing Nok-du to ignore her and pretend to go back to sleep. Dong-joo denies and beg him to help before the guard wakes up and catches her trying to escape. Satisfied at forcing her to say, “Hyung-nim, please,” Nok-du pulled Dong-joo back in causing her to hit her head.
Nok-du lays back down and say that it is not a bad situation given that he is finally in Hanyang so he can find out himself, who he is.
The King bolt awake in cold sweat from his nightmare. Flashback shows his younger self suffocating/killing a baby in his arm.
In the cell, Nok-du awakes up to Dong-joo whimpering in her sleep, calling out to her mother. He pats her shoulder to calm her and cover her with his outer wear to keep her warm. However, as the morning comes, we see the two had curled up next to each other, Nok-du head on Dong-joo’s arm and Dong-joo has her leg over his, causing the two to jump in alarm at their proximity.
The guard comes to take them for questioning and as Dong-joo see other prisoner’s being tortured, it triggers her memories of family’s massacre. When the minister interrogates her reason for being the city and warned that she would die if she were to lie, causing Dong-joo to recalled her mother’s last word for her to live.
The guard pull out his sword and point it towards Dong-joo as the minister demand she answers the question. Seeing her nervousness, Nok-du sigh and take a stand (and I swoon at that little slo-mo), demanding to see the King who stop in his track as he is passing by. The minister question why he wants to see the King to which Nok-du tells him that a traitor would not take a rock to throw and public declare their grievance. He claims it is useless to arrest civilian to question based on an arrow that they do not know when and where it came from. Instead suggest that the King should flaunt his gracious nature or at least pretend to be so the people can be moved by him and pledge their loyalty to the kingdom.
Although the King scoff at its lowly method but still see it as a persuasive one thus ordering Minister Heo to follow through with Nok-du’s suggestion however to not let the elder man lived.
Free, Nok-du suggested as a thank you to buy him soup with rice when he suddenly sees a noblewoman cover in a blue cloak heading towards them. Seeing that she was reaching inside, thinking that she was pulling a weapon at them, Nok-du pushes Dong-joo aside, only for the woman to grab her handkerchief.
The two ends up bickering again until Dong-joo remember the letter she had left and runs off, warning Nok-du not to let her bump into him again or she would show him who’s boss.
Nok-du pulls out the cloak to see a crescent moon symbol and wonder where he should go to find it but then thinks that the assassin would be looking for him as well. Nok-du ends up staying at the inn as the assassin looks on.
He sits in his room, wondering when the assassin would come so he can get it over with and return home to his father and brother. He sits and remember when he and his brother were being punished. Their father reminding his brother to keep Nok-du away from boat. Defiantly, Nok-du question why he is not allowed to read, write, or row on boat as he wanted too which his father does not answer him. Later that night, he sees his mother tending to his brother’s leg.
The innkeeper comes with food and drink, offering it to him for free since a customer did not eat it.Shortly later, Nok-du stagger out of his room into the street in pain. The assassin follows him but before she can attack him, Nok-du collapse in front of two guards. One of the guards claims he is dead and tell the other one to run back and get their chief.
The assassin returns to the inn and check that Nok-du did drink all the alcohol in the bottle before she kills the innkeeper.
The guard return with the chief only to find the other guard unconscious with Nok-du nowhere to be found. The assassin through the forest with Nok-du following close behind.