Have you ever experienced the sensation of a fly buzzing in your ear? The itchy feeling of vibrations shooting from your ear canals throughout the rest of your body? An average person will do his or her best to shoo it away, but the pesky vermin will only come back with a vengeance, undeterred by the human's growing irritation. 

This was exactly how Hoya felt as he walked towards Park Hana's hospital room. Frustrated with the urge to swat away a fly. Only it wasn't an insect buzzing in his ear, it was the senior nurse assigned to Hana's care. 

But then again, considering the circumstances, what was the difference?

"You can't go in there," the nurse squawked in his ear for what seemed like the eighth time that day. Her short legs, which were like blocks of firewood compared to Hoya's much longer limbs, made it difficult for her to match his hurried pace. "She only got out of surgery yesterday. Do you really think it's appropriate to interview a patient under such conditions?"

"Yes, I spoke to another nurse about that," Hoya responded as pleasantly as he could. His mother had always told him to be gracious to people, even if you wanted nothing more than to punch them in the face. As he turned the corner, he couldn't help but feel a newfound respect for her patience and tolerance level. "He said her injuries weren't life-threatening at all and that her surgery would have only been a minor one. A fractured arm, was it? From my understanding, it would have been alright to talk to her last night." 

"Don't be ridiculous; you need to let her rest for at least three days," the nurse argued back. Her face was growing redder and redder by the second- though from physical exertion or increasing agitation, Hoya didn't know. 

He took a deep breath. 'Be gracious,' he reminded himself, then glanced at the medic. 

"I'm not sure if you've read the news, but we're in the middle of a serious murder inquiry. We simply can't afford to wait another few days to speak with a person connected to our case, surgery patient or not. Of course, I've already cleared everything with the doctor in charge of her ward. Dr. Shim granted permission for her audience, as long as I don't do or say anything to agitate her. I gave my word that I wouldn't. And I promise, I'll do my best to keep the interview as short as possible."

The nurse wavered. Clearly his words had struck a chord with her. "Ms. Park mustn't be disturbed-"

"Why don't we ask her?" Hoya interrupted smoothly. He had arrived at his destination, room 522. Park Hana's room. "If she's feeling tired then I'll come back another day, but if not, I'll talk to her about what I need to know. I'm sure it won't take long."

Without waiting for an answer, he knocked on the door and called to the patient inside. 

"Ms. Park? Are you awake?"

A few seconds passed before he heard a low voice. "Yes. Come in."

Hoya pushed the door open. He politely gestured for the nurse to enter before him- she did so with a displeased frown tugging - then walked inside himself. "Hello, Ms. Park. My name is Lee Howon and I'm an agent of the CSI force." Stopping at the edge of her bed, he held up his ID for her to see. 

He continued, "I was wondering if you could spare a few minutes right now? I have some questions I'd like to ask you regarding a murder case." 

At this point the nurse, who had been impressively quiet for the thirty seconds they'd been in there, interjected in an unnecessarily loud voice. "Dear, you can always say no if you don't want to. You need your rest more than anything. Remember that your recovery is the top priority right now."

Hana shrugged her good shoulder. "It's fine. It's not like I'm doing anything now." She flickered her gaze towards her broken arm before turning back to the nurse. 

"But if you don't mind, could you get me some painkillers? My arm is still feeling sore, even when I keep it still." 

"Of course. I'll be right back." The nurse fussed over her like a mother hen would, even though the bedridden woman was probably ten years her senior. Shooting a final scowl in Hoya's direction, she told Hana she would return in five minutes and left the room.

"Well, then," Hoya cleared his throat. He hoped it would be a lot longer than five minutes before the medic returned. With long strides he walked towards the door, closing it shut before returning to Park Hana's side.

"Is your arm bothering you a lot?" he asked, out of both courtesy and concern. He seated himself in the empty chair beside the patient's bed.

Hana shrugged again. "It's not as bad as it looks. To be honest I only said it to get that nurse out of here. She means well, but sometimes it's nice to have peace and quiet." 

The agent gave a wry smile. "It certainly is," he agreed wholeheartedly. He could still feel the buzz of the nurse's nagging in his ears.

His companion fell silent, staring down at her broken limb. She was obviously waiting for her visitor to do his part and proceed with the interview. Hoya took the chance to study the injured lady. She looked exactly as she had in the photograph Youngjae had given him. Mousy hair, wrinkled forehead, plain features... But mostly tired. So, so very tired. Because of her injuries? A lack of sleep? No, Hoya instinctively knew it wasn't the kind of weariness that could be cured with rest and good food. Park Hana was being exhausted by life itself. It was clear that somewhere along the road she had stopped resisting, and was now waiting for time to end everything for her.

Hoya couldn't help but pity her. 'This woman,' he thought sadly, 'Is just one of countless others whose flames have burned out...' 

In the end, it was Hana who broke the silence. "So what did you want to ask me?"

"Ah, yes. This shouldn't take too long, I hope," Hoya answered in a business-like tone. He pushed away his feelings of sympathy in favour of a professional composure. "I have some questions regarding your step-brother."

For the first time since his arrival, a flicker of surprise showed through Hana's tiredness. "Jongin? What does he have to do with anything?"

"We have reason to believe Kim Jongin is connected to our case." The detective quickly explained the scientist's link to the first victim, Lee Seonwoong. "But before we go any further, I'd like to know: where were you during the past few weeks? You weren't at home and nobody we talked to knew what you were doing, not even your son. All he knew was that it was normal for you to sometimes disappear for a week or so." 

Hana nodded. "That's right, I do. I'm a private person, and changes in scenery help me to think about things. Often times I go to Busan to look at the sea, but this time I decided to go to Cheongju instead." She gave him the name and address of the hotel she'd stayed at.

Hoya pulled his pocket notebook out and jotted down the information. "Do you always travel without telling anybody? What if you get into an emergency? As a son myself, I'd certainly want to know where my parents were going off to," he added, trying to keep his words less critical and more diplomatic. As irresponsible as Park Hana seemed, it wouldn't help if he started pointing fingers in her direction. 

Luckily for him, she didn't appear to be offended. "My son is twenty-seven years old and married," Hana said simply. "He doesn't need me burdening him when he's trying to make a life for himself. Besides, I'm an independent person. I can get by on my own or with very little help from others." 

"I see." Hoya wasn't shocked at all by what he was hearing. He remembered that the son hadn't been particularly upset when they'd first called to question him. "In that case, let's proceed with the interview. Could you start by telling me why Jongin was in your apartment when we found him? Was he living with you?"

"You could say that." The older woman paused as if trying to sift through her memories. "Jongin and I were never close. As you probably already know, our parents divorced after only three years of marriage. Naturally I stayed with my father and my step-brother left with his mother. We didn't bother staying in touch afterwards. None of us had a reason to.

"But about three months ago," she continued, "I received a letter from him. I suppose my father gave him my address. Jongin had written that he needed a place to stay as his lease was coming to an end, and he had nowhere else to go. He was sorry that after all these years he only contacted me to ask for a favour, but it was very sudden and I was the only person he could think to ask." 

"So you agreed right away to let him stay with you?" 

Hana shook her head. "I was hesitant at first. Like I said, I prefer to be alone. I even suggested a few places that I knew were available for rent. But he was very persistent and said he'd rather stay with somebody he was comfortable with. In the end I agreed. I didn't have the heart to turn down family, even if that family had technically only lasted for a few years. It's been a little over a month since he moved in."

Hoya glanced at her with a thoughtful expression. "What was he like as a child? When your parents were still together."

"Curious, I suppose. Jongin was always reading books about the ecosystem or astronomy or whatnot, trying to answer the questions of why and how. Mostly he kept to himself. Though I have to admit I wasn't interested in getting to know him. I'm afraid neither of us tried very hard to make friends with the other." 

"And yet he chose to ask for your help after years of no contact?" Hoya wondered aloud.

"Maybe he really didn't have anybody else to ask," Hana offered with no real enthusiasm. 

"Maybe." The detective checked his watch. Ten minutes had passed and there was no sign of that busybody nurse. He hoped it remained that way. "You said he's been staying with you for about a month now. What has he been up to during that time?" 

"I'm not sure. Most of the time he stays in his room or I'm at work, so we don't see much of each other. But..." Again, Hana hesitated.

"Yes?" Hoya encouraged. He sensed she was going to tell him something big, something that could actually help their investigation. He subtly shifted in his seat, trying not to scare her off with his impatience.

The injured lady glanced at him from the corner of her eye. "I don't know if this will be of much use, but there's a man who's been trying to contact Jongin. He started phoning my apartment about five days after my step-brother moved in. I didn't catch his name, but a week afterwards I overheard Jongin talking on the phone, presumably to that man. Zhang Yixing, I think his name was. I don't remember Jongin's exact words, but they were something like case twenty-one having nothing to do with the murders and to stop calling him... And no, before you ask, I have no idea what he meant by that."

Hoya scribbled points into his notebook, but he was barely paying attention to what he was writing. His mind was too busy racing with frenzied thoughts. Case twenty-one? As in the Case 21, the mysterious mockingbird project that the agents were trying to uncover? Hoya furrowed his brows. Those notes had been discovered in Lee Seonwoong's house. Seonwoong and Kim Jongin had been research partners, but the agents had assumed only the former had been involved with Case 21... Dammit, they had assumed... 

The detective stood abruptly from his chair. "Thank you for your help," he told Hana. He felt more agitated than ever- Case 21. That was the missing piece. If they could figure out what it was, they'd have the entire puzzle solved, he just knew it. But first he needed to talk to Kim Jongin, and he needed to do it fast. "If I have any more questions, I'll be sure to contact you. In the meantime, I wish you a speedy recovery."

"Thank you." Hana didn't look surprised or even relieved at his sudden departure. On the contrary, she appeared to be even more tired than before. "I'll be here if you need me."

It was when Hoya was about to close the door behind him that she called him back inside. "One last thing, Inspector..." 

Hoya glanced over his shoulder. "Yes, Ms. Park?"

Hana had closed her eyes. "He's not a bad person, that Jongin. I don't know what he's up to or what he did in the past, but his heart's in the right place. Even I, the estranged step-sister, know that much."

"I'll keep that in mind," Hoya answered after a pause. "Have a good day, Ms. Park." He stepped outside and pulled the door gently to a close. After staring at it for a moment, he remembered with a jolt that he had an urgent phone call to make to the station cells. The agent pulled his phone from his pocket and quickly found the number he was looking for. 

"Hello, Deputy Chief Jeon speaking."

"Chief, this is Lee Howon from the crime scene unit." As he spoke, Hoya strode down the hall towards the elevators. "Could you arrange for me to speak with Kim Jongin today? I'm afraid it's rather urgent."

"I'm sorry, but that's not possible. Kim Jongin was released on bail just a few hours ago." 

Hoya stopped in his tracks. "He was what?"

"He was released," the deputy chief repeated. "Somebody came by this morning to bail Kim Jongin out. Without charge, I might add. The return date is in a month, but I don't think there will be any charges against him. The investigating team is ruling this as a self-defence case." 

Hoya couldn't believe what he was hearing. No, no, no, no. Jongin was out? He had escaped back into the world? They had been so close, at least a fraction of a step closer to finding the Mockingbird. And now he was gone? What had happened to Lady Luck playing in their favour?

"And who exactly was the person who bailed him out?" Hoya managed to ask after a brief moment.

The chief's answer stunned him back into silence.

"He said his name was Zhang Yixing."

[A/N] Just a short update to welcome a new week :) This is like the turning point of the story- things are going to get dramatic very soon! On another note, I'm seriously tempted into writing a new CSI story starring Bangtan. My love for them is too strong ;-;

Happy reading, you lovely people <3