Moon Ryeong has no idea how it all began, but she surprisingly received some unexpected guests at Jae Rim's house. There are three guests, one of whom the chairman recognizes, and the other two whom he has never met before. However, Jae Rim is pleased that he was able to meet with Moon Ryeong's 'friend' and openly welcome them into his home. The three guests are now standing in front of the door, two of them smiling broadly, while the sole detective is distressed by the atmosphere.
   "Hello and good afternoon! We bring some wine to share "Min Seol cheerfully displays a bottle of red wine.
    "Sorry to interrupt your time," Changmin says to Moon Ryeong and Jae Rim, but the young man doesn't appear sorry.
   "Are we allowed to enter the house?" Min Seol keeps going.
   "Sure," Jae Rim said, allowing the visitor to enter his home and follow the two of them from behind, while Moon Ryeong remains outside, demanding an explanation from Lee Sung Gi, the detective.
    "I never expected you to come here with them when you asked me where I was." The lady crossed her arms and stared intently at the detective.
   "I apologize; they are both very excited to see the man who will marry you. When they see your message, they immediately suggest that you meet with them here "The detective describes the situation. He'd been here before, when he assisted the chairman with Ohn Jung Sik's case, so he knows exactly where Song Jae Rim lives.
    Moon Ryeong frowned, wondering how the two young people could have read her message to Sung Gi. But, based on their easygoing and meddling personalities, she suspects that Min Seol and Changmin might sneak a peek on his phone while Sung Gi reads it. As a result, she decides not to pursue it any further with the detective.
  Moon Ryeong and Sung Gi then join the others in entering the house. Min Seol and Changmin are already seated at the table, enjoying wine and a feast prepared by Jae Rim. They appear to consider themselves to be at home. Lee Sung Gi shakes his head as he observes their actions, while the lady approaches Jae Rim with a guilty expression.
   "They're quite funny," Jae Rim says of the two young people's behavior. It's been a long time since he's met people who are as energetic as them and have nothing to fear. As a result, it's quite refreshing for him.
   "We're not coming here to eat," Sung Gi smacks his great granddaughter's head to stop her from being so relaxed and enjoying her time.
   "Oh, great grandfather, it hurt." Min Seol was sulking and pouting her lower lip. When Changmin saw how the vampire mercilessly hit his own great grand daughter, he immediately put the food in his hand and smiled foolishly at the detective, apologizing.
  "Don't be too hard on us; we've been on the run since spying on that damn professor. We need to eat and refuel our batteries." Min Seol is still negotiating with the vampire. Lee Sung Gi can only sigh deeply as he realizes she is correct. The three of them had not eaten anything while stalking a professor whom Changmin suspected of being involved in the vampire DNA mutation case.
   "Whose professor is this?" Moon Ryeong becomes intrigued and approaches the three of them.
   "To be honest, we might have found the culprit in our current case. People who create vampires through DNA mutation...." Lee Sung Gi does not finish his sentence because he is aware of Song Jae Rim's presence. He is unsure whether they can discuss this in front of the chairman.
    Moon Ryeong is looking at Jae Rim while following Sung Gi's gaze. She understands why Sung Gi is hesitant to proceed. After all, Jae Rim is just a regular person who has nothing to do with the case. Involving the chairman in the case may be harmful to them and endanger his safety.
  "Don't be concerned... I'd like to continue working from my own office. You are free to discuss whatever you want without being bothered by me." Jae Rim becomes understanding and leaves them alone. He understands that there is a line he cannot cross regarding the vampire's life. As a result, he avoids interfering in their affairs, even though he would gladly assist Moon Ryeong if she needed him in any way.
   Jae Rim enters his private office and creates a space for them to converse. They begin to tell Moon Ryeong about their new discoveries. Yesterday, Changmin asked Min Seol and Sung Gi to accompany him as he spied on Prof Kang Dong Won, a former colleague of his. When he worked in their department, the professor was always wary of him.
   He is the one who promoted Dr Lim In Suk and transported him to a location only he knows about. Changmin is certain that Prof Kang Dong Won has something to do with the disappearance of Dr Lim. They had been spying on the professor and waiting for him to emerge from the laboratory building. Changmin and Min Seol are in the same car, while Sung Gi is on the other.
     When the professor appeared and drove away from the building, Changmin got out of the car and entered the building, while Sung Gi followed the professor. Min Seol is standing outside, watching the surroundings and ready to intervene if something bad happens to the young scientist. Changmin used Dr Lim In Suk's stolen access card to gain access to the laboratorium. He then goes to the professor's office, looking for anything in there.
   The door to the professor's room is password-protected. Changmin enters a series number of a birthday date from an idol from a popular girlband in an attempt to guess the password. He ever caught the professor listening to the idol's famous solo debut and discovered a cover album of her on his table. As a result, he could make a wild guess that the cold and cruel professor is a fan of that idol.
    "click" The sound of an unlocked door makes Changmin's eyes rounder, and he is surprised that his guess was correct.
  "Daebak! That pyscho is a huge fan of Jennie~~~ Sololo lolo" Changmin enters the professor's office while singing and performing a dance to imitate the female idol. Even in the office, he finds time to dance.
    "Changmin, Changmin! Focus!" Kim Min Seol, who has audio and video connected to a device on Changmin's body, can clearly see that the young scientist is playing around while he needs to search the office and leave it immediately.
    Changmin laughs when he hears Min Seol's angry voice. He then went straight to the professor's table, looking for the documents there. He meticulously searches through all documents one by one.
   "Oh!" exclaims the young scientist, surprised.
   "Did you discover anything?" Min Seol is ecstatic about the possibility of discovering something new about the case.
    "Look! He's a complete freak. He gets the entire debut album of Jennie... Sololololo "Changmin, on the other hand, continues to play around for a while, causing the young girl to exhale in frustration.
   When Changmin cannot find anything unusual in the document on the table, he begins rummaging through the cabinet table and discovers a locked hidden safe inside.
   "I believe we might find something special inside; could you open the safe?" Changmin inquires of Min Seol.
    The young girl instructs him to put on the device she has prepared for such a situation, and he does so. Min Seol immediately typed a series of numbers and abjad and created a script to hack into the safe using the computer that was connected to the device. She can see the loading progress, and then the safe is unlocked. She embodies success.
   Changmin then takes the document inside to gain access to the confidential information. When he reads the document, his face is tense and serious. He discovers something he never expected to find.
  "This is the document that I retrieve from the safe. There is information on a list of scientists who have been chosen to be promoted to a confidential project that they keep hidden from others." Changmin showed the document to Moon Ryeong so she could read it.
   "There are also details of the project related to vampires," he continues solemnly.
   Moon Ryeong carefully reads the document and discovers that Prof Maurice Sylvestre founded a special organization that recruited many talented scientists from around the world. The project claims that they want to create an invincible human who cannot be defeated by anything in order to create an army capable of protecting their country.
   The project had been in the works for decades and had seen numerous setbacks. There is also a document that describes a vampire trait that they believe is ideal for creating an invincible soul. They have been conducting extensive research on vampires and intend to use their blood to create a virus that can be injected into the subject of their selection. They also write a suitable subject characteristic that is required for the experiment to be successful.
  They succeeded in creating a vampire-like creature with a fang, great strength, and the speed of light a month ago, but it still failed because the subject is too wild and cannot be controlled. As a result, they decide to get rid of the first subject. To eliminate the failed subject, they use the sunsa bullet they created.
   "The corpse on the mountain appears to be a victim of the subject being discussed here. They burn the corpse so they don't turn into uncontrollable vampires." After relating one case to another, Sung Gi makes an assumption.
 "I'm not sure how they were able to obtain vampire blood to create the virus, but I believe you should be concerned. We don't know if they can target you for your blood as well "Sung Gi keeps going. He would also notify his family.
   "However," Changmin continues,
   "the pure blood vampire is mostly who they target." His words immediately made Moon Ryeong think of a specific creature.
   "Helios," she says softly. He is the only pure vampire on the planet.
   "I suppose you should warn him about this as well," the detective says. Moon Ryeong remains silent. They are no longer in a relationship and thus cannot communicate with each other, so she cannot respond to his statement. But she is also concerned about the great vampire.
   "I've been looking for Prof Maurice Sylvestre, the project's leader. He is a gifted scientist who has created hundreds of complex chemistry compounds since he was a young. He has previously received a noble award for his achievements." Min Seol joins the discussion.
   "He was born in France and goes by the name Maurice Smith Sylvestre. Prof Kang appears to have had a secret meeting with him yesterday, implying that he is currently in Korea." Sung Gi presents Moon Ryeong with a portrait of Prof Kang and Prof Sylvestre. In a European restaurant, she notices a Korean man conversing with a foreign man. She squints her eyes as she examines the photographs of foreign scientists. The foreign man appears to be familiar to her in some way.
  "Do you have a better look at this person?" Moon Ryeong inquired while pointing to the foreign professor.
   "Ah, a moment please," Min Seol says as she searches on her iPad and scrolls through the images.
    She has his complete personal information as well as his research photographs. She also took pictures of the professor at another social event he attended and gave them to Moon Ryeong.
   Moon Ryeong received the iPad from Min Seol and was looking through the photos. She is surprised to learn that the professor who is planning a cruel project is not only familiar with her but has also been living under the same roof with her for the past few months.
   "Doctor Smith is Maurice Smith Sylvestre?" When she calls his name, her voice shakes. The enemy who has been endangering their lives and the lives of everyone around them, the person behind the massacre on their mansion, is not any other person but the one who is also allowing her to walk in the sun during the day. She has finally realized.
   "Helios is in danger!"