At Bukhansan,

Sungmin ducks behind the tree outside Kyuhyun's Headquarter. Next to him, two other girls also snoop around with him. Inside the Headquarter, Kyuhyun is alone with a girl they have never seen before. 

"Who do you think she is?" The girl standing closer to Sungmin raises her head to the other girl. In her eyes, a tinge of curiosity and envy can be seen.

"Who knows! I have the same information as you do!"

The other girl turns to her. Then, with a careful look, she turns to Sungmin, "Do you know, Lee doryeonnim?"

Sungmin slightly shakes his head, his eyes never leaving the windows and main entrance to the Headquarter. He searches hard in his mind for any information, any memory he could have of the girl, but to no avail. He has never seen her before in his life.

"Did you see how beautiful she looks?" The first girl speaks up again. "She was so graceful when she walked in there! She must be a daughter of some ministers!"

"No wonder..." she hesitates while stealing a glance at Sungmin.

"What?" Sungmin turns to look at them when he feels two pairs of eyes staring at him.

"Nothing, doryeonnim!" They both answer in sync.

But he can still hear the whisper of the second girl as quiet as a cloud: "Yah, stop it. It's bad enough for us. We are only Master's admirers. Imagine how hard it must be to see your ex..."

"Yah!" Sungmin cuts her off right when she is about to utter the most important word, "I was never Kyuhyun's ex-boyfriend!"

The two girls look at him in shock, not only because of the fact that he could hear them whisper under their breathes, but also because of the information just given to them.

"We didn't say anything, doryeonnim!" They turn to him, in sync again.

"It's true. I'm not his ex-boyfriend." He does not know why he has to keep explaining to them.

"Yes, doryeonnim."

"We're just friends."

"Yes, you're just friends."

The two girls nod aggressively at him, even though they are now even more confused at the things that their Master does for his friend.

"Who's friends with whom?" A warm and stern voice suddenly appears in front of them.

"Kyuhyun!"

"Master!"

"Master!"

The three are startled by the same person they were spying on. The two girls quickly excuse themselves, leaving Sungmin alone to answer to those curious and inquiring eyes.

"Tell me, who's friends with whom?" Kyuhyun takes one step closer to Sungmin, their faces so close to each other he can feel the other's breath on his face.

"Nothing, Kyuhyun! We were talking about the students at the school!"

Kyuhyun furrows his brows at him, then, when he cannot detect anything out of the ordinary, he turns to walk in the opposite direction.

But Sungmin dashes to catch up to him.

"Hey Kyuhyun," he studies Kyuhyun's face carefully, "who was that girl in there? Was she...? Did you...?" He fails to finish his own sentences.

Kyuhyun stops in his steps and looks at him solemnly.

"You saw her?"

Sungmin slightly nods at him.

Kyuhyun looks into his eyes carefully for a second, then takes a deep breath as if about to announce the most important news.

"I did not want you to find out this way, Sungmin." 

He comes closer to Sungmin, then whispers as low as he can into the other's ears. Sungmin's heart skips a beat. He swallows hard to prepare for the worst news anyone could have to take.

"She is the Jos' daughter." Sungmin feels his ear burning at the other's whisper. He turns to see a grin on Kyuhyun's face.

"Yah, why did you have to say it like that!" Sungmin lightly taps on his arm out of annoyance. "I thought... I thought..."

"Thought what?"

Kyuhyun smirks and looks at him amusingly. In his head, an answer is as clear as day, but he still wants to tease it out of the innocent man in front of him.

"Yah, Jo Kyuhyun, stop teasing me!" Sungmin protests when he sees the amusement in Kyuhyun's eyes.

"Then stop making it so easy," he takes a step back, the grin never leaving his face and the amusement never leaving his eyes.

The Jos do have a daughter after they took him in. But she has always stayed in Hamheung, away from the capital, so Sungmin has only heard about her. He had never seen her in person before. 

"Kyuhyun ah," he continues walking with the other, "Other people might not know it, but you technically are not blood related. You are a single man, she is a single woman. You staying in the same room with her alone might not be proper..."

"She has a fiance at home, Sungmin." Kyuhyun stops to look at him.

"Oh." Sungmin looks at him in surprise.

"What do you think?" Kyuhyun smirks at him again.

Sungmin feels himself blushing at the other's amused look.

"I thought maybe..." He stutters.

"What?" Kyuhyun remains his grin as if watching the most interesting entertainment. He takes another step closer to the other, so close that he could feel the sweet scent of the bright pink flower on Sungmin.

"So what was she doing here?" Sungmin quickly changes the subject.

"Just visiting me and bringing news from Hamheung."

"Are the Jos okay?"

"Yeah, they are well."

"Lee doryeonnim."

Sol's voice suddenly interrupts their seemingly endless conversation. Sol looks at them carefully before speaking up again.

"Your father sent a letter."

That night, Sungmin and Kyuhyun await Doctor Shin's responses impatiently.

They had received the letter from Lee Youngwoon, enclosed with the bottle of liquid that Heechul had held in his hand until he died. The bottle must have had some message he wanted to convey to them. They immediately called for Doctor Shin, the best doctor in all of Hanyang, and probably in Joseon, to examine the bottle. 

"This is a kind of poison," the doctor concludes after hours of thorough examination and research through his books, "it is not lethal, however. It will only leave some marks on people who have inhaled it in close distance. The marks might look like blood veins on the victim's arms and legs, and will not go away unless the victim takes an antidote. This is an extremely sophisticated and rare poison, doryeonnim. Whoever made this dose in this bottle must be really skilled in potions."

With that information, Sungmin and Kyuhyun leave Bukhansan to reunite with Lee Youngwoon. At the gate of the Lee's residence, they find Lee Youngwoon standing solemnly, his eyes staring into an indefinite emptiness. Sungmin has not seen his father like that ever since the tragedy with the Jun family.

"Abeonim?" Sungmin gently calls out to his father, "Abeonim, are you okay?"

"Sungmin, Kyuhyun," Lee Youngwoon seems to be pulled back into reality by his son's voice, "did you find out anything about the bottle?"

Sungmin slightly nods his head. Then, he and Kyuhyun take turns briefing Lee Youngwoon on Doctor Shin's findings.

"I saw those marks on Heechul's arms when I found him. I examined the rest of the followers. None had such marks on their arms and legs. That means none of them were anywhere close to Heechul when spread that poison. So, the only other person who will have those marks is their killer."

Lee Youngwoon's voice is distant, cold, and determined.

Sungmin and Kyuhyun nod at his conclusion.

Suddenly, Lee Youngwoon looks up at them, as if just arriving at another conclusion.

"We have to go to Leeteuk's residence. To find a way to contact him and notify him of these revelations."

Lee Youngwoon's voice is dry and stern. Neither Sungmin nor Kyuhyun says anything but only nod at his instruction.

Leeteuk's residence is as quiet and serene as a temple. Sungmin cannot recall the last time he was here. In his memories, he has always seen Leeteuk at either Seowangmyeong or the Lee's residence.

Leeteuk's residence only had fewer than five servants. When they arrive at the residence, it is close to midnight. All the servants are already resting in their quarter.

Lee Youngwoon's purpose in coming to Leeteuk's residence is to find a way to contact Leeteuk through his servants. Despite knowing Leeteuk all these years, he is surprised that he does not even know where his relatives are.

As he is about to enter the servants' quarter, Lee Youngwoon's eyes catch a weak ray of light coming from Leeteuk's room. In the room, a tall and slim shadow can be seen sitting as still as a statue.

"Leeteuk?"

With no hesitation, Lee Youngwoon approaches the dimly lit room.

"Young... Youngwoon ah, what are you doing here?"

"You're back?"

Lee Youngwoon ignores Leeteuk's question.

"Uhm, yes, I just got back."

Leeteuk's voice is dry. He tries his best to maintain a calm exterior.

"Leeteuk, there is something I have to..."

Lee Youngwoon's words are suddenly cut off by a look at the other. In the dark room, Leeteuk was sitting at a table, one of his bare arms on the table. As Lee Youngwoon, Sungmin and Kyuhyun enter the room, Leeteuk quickly stands up and rolls his sleeves down his arms.

On Leeteuk's arm, a pattern of vein-like marks was visible. They look exactly like the marks on Heechul's arms, which will forever be scarved into Lee Youngwoon's mind.

"The only other person who will have those marks is their killer."

That was his own conclusion when he heard Doctor Shin's findings.

Lee Youngwoon takes one step back from Leeteuk. His arms reach out in front of Sungmin and Kyuhyun.

"Sungmin, Kyuhyun, stay behind me."

"Seonsaengnim."

"Abeonim, what's wrong?"

In the room, Leeteuk stands still.

"Where were you yesterday, Leeteuk?"

Lee Youngwoon's voice has become colder and distant.

"What do you mean, Youngwoon?"

"Tell me, where were you yesterday, Leeteuk?" 

Lee Youngwoon repeats, each word echoing in the cold and dimly lit room.

"I was in my hometown to see my relatives. I already told you that."

"Show me your arms."

"What?"

"Show me your arms!"

This is the first time in a long time that Sungmin has heard his father raise his voice. Lee Youngwoon's hands clench in a fist, and his eyes shoot daggers towards Leeteuk.

"No." Leeteuk's eyes remain determined.

Lee Youngwoon lets out a deep sigh.

"Yesterday, someone attacked the Haeju rebels. Most of the group was injured. And Heechul and Dongchun are..."

Lee Youngwoon pauses, his voice shaky.

"Heechul and Dongchun are dead, Leeteuk." He closes his eyes for a second to compose himself. "Were you there?"

Leeteuk's eyes shift to the indefinite emptiness behind Lee Youngwoon.

"Leeteuk, if you don't say anything and don't show me your arms, I will take it as you were there, and you were their killer."

Behind Lee Youngwoon, Sungmin and Kyuhyun widen their eyes.

"Stop this nonsense, Youngwoon."

"Then tell me you did not kill Heechul, Leeteuk."

Youngwoon knows that Leeteuk could never lie to him. The silence between them feels lethal.

In front of Leeteuk, Lee Youngwoon starts to draw out his sword.

"Who are you?"

Youngwoon's eyes and voice pierce through Leeteuk's heart.

"Youngwoon ah..."

"Stop saying my name! Is Leeteuk even your real name?"

In a quick second, the last tiny tinge of hope seems to have disappeared from Leeteuk's eyes.

"My real name is Park Jungsu."

"Park...? Of the Park family?"

"I'm not related to them. But they brought me home and trained me."

"You're their guard dog."

Lee Youngwoon scoffs at the revelation.

Leeteuk's eyes have become harder.

"What are you doing here? With us?"

"My mission was to gather information on you after the purge of the Jun family. Choi Oongshik, the King's Uncle, has always suspected you to be more involved with Jun Kihong's politics than you showed. So, I was tasked with watching you and getting information on you."

Lee Youngwoon feels his heart beating faster and faster with each of the other's words. 

"Did you tell them everything?"

"No, not everything."

Leeteuk shifts his eyes to Kyuhyun and Sungmin: "Their secrets are safe."

"I only told them trivial stuff, like when you recruited Kim Heechul from the Kims in Haeju at Seowangmyeong, or when you gave a scholarship to a peasant like Lee Hyukjae."

"Why didn't you tell them everything?"

More silence follows. Leeteuk looks straight into the other's eyes.

"Why do you think, Youngwoon?"

"I honestly don't know."

Lee Youngwoon shakes his head. In his eyes, Leeteuk can see a clear hint of anger, disbelief, and disappointment.

"Did you tell them about the Children of the Mountains' base in Bukhansan?"

"No."

Leeteuk quickly shakes his head.

"Youngwoon ah, there is something..."

Leeteuk could not finish his sentence, as he immediately feels something cold and sharp piercing through his stomach. Leeteuk's eyes remain glued on Lee Youngwoon.

He always knew this day would come.

He immediately pushes Youngwoon away, the blade coldly leaving his body. A hot stream of blood starts dripping onto the floor.

Behind Lee Youngwoon, Kyuhyun and Sungmin also draw out their swords.

Leeteuk easily avoids their attacks. As Kyuhyun comes at him a second time, he pulls out five darts from his pocket and swiftly throws them at the other. As Kyuhyun tries to dodge the darts, Leeteuk takes his sword and incapacitates him.

"Kyuhyun!"

Sungmin exclaims. He quickly comes to Kyuhyun's side, his eyes never leaving the enemy.

"Sungmin," Lee Youngwoon approaches with his sword ready, "take Kyuhyun back to Bukhansan first."

"But, abeonim..."

"No buts, Sungmin! I will follow after I finish things with him."

Going by his father's eyes and voice, Sungmin knows not to disobey him. He quickly helps Kyuhyun stand up and walk out to the front yard.

"Leave them alone, Leeteuk."

"I was never gonna hurt them, Youngwoon."

"I will make sure you never will, Leeteuk."

As he finishes speaking, Lee Youngwoon picks up one of the candles nearby and throws it onto the ground. The fire from the candle slowly spreads onto the wooden floor, table, door, and walls. As Leeteuk is stunned at the scene surrounding him, Lee Youngwoon stabs him again, this time on his chest. But the other does not seem to be fighting him off.

"Goodbye, Leeteuk."

As he walks out of the door, Lee Youngwoon starts to hear a quiet laugh from the other. Then, the quiet laugh becomes a series of full cackles. Leeteuk lies on the floor, his blood starting to soak into the wooden floor.

"Youngwoon ah, have I ever told you the one philosophy I have been taught at the Parks since I was a kid?"

Lee Youngwoon stops in his tracks.

"My Master has always told me, every man is an island, Youngwoon ah. Friendship, family, and love. They are all an illusion. In the end, any man would always choose money, power, and status over sentiments. And I have lived my life believing in that philosophy. Until the day I met you."

Youngwoon slightly turns around to look at the other.

"If every man is an island, Leeteuk ah," he speaks firmly, "then this is just me burning all the bridges."

With that, Lee Youngwoon turns his back on him and walks out for good.

A tear quietly spills out of Leeteuk's eyes, onto the cold floor.

For the second time in his life, he has lost the precious bridges that have rescued him from the lonely island that was his life.