He couldn’t stop thinking about it. The scuffle in the dark, on the ground below him. Sehun’s gasp, coming just before Chanyeol had reached them. The way he’d tried to get up, then fallen back with that awful choking noise. The way the shadows around the hand holding his abdomen had resolved into the hilt of the knife. All of it was suffused with blinding, suffocating horror.

Chanyeol recognized that his horror was disproportionate to the situation. Sehun was in surgery, but the doctors were confident of a positive outcome. The horror was leeching in from elsewhere, from the last time he’d had an officer down, and it kept dragging him back to that night, and all the pain and rage and helplessness that went with it.

“Chanyeol?”

Coming out of his thoughts felt like breaking the surface of dark water. Seulgi was standing in front of him. When Chanyeol focused on her, she gave him a small smile and handed him a disposable coffee cup. Automatically Chanyeol took it, and Seulgi sat down beside him.

“How are you doing?” she asked. Chanyeol looked away, down at the drink she’d given him. The warmth of it began to seep through the cup and into his fingers. He had no idea how to answer that question.

“Thanks for taking command,” he said instead. “I wasn’t thinking clearly.”

Seulgi nodded. He was aware of her eyes on him. He took a sip of the coffee. It was milky and oversweet. Sugar for shock, he thought grimly. Seulgi was probably right to give it to him. He hadn’t put up a good showing back there. He hadn’t kept his head. Police officers were supposed to stay detached and behave rationally, but fear and emotion had taken him over. Not what a unit leader was supposed to do. He couldn’t keep his team safe that way.

Seulgi put a hand on his arm. “I know you’re doing the best you can,” she said gently, and at those words Chanyeol was suddenly back in the last vision he’d had of Baekhyun, in Seungwan’s hotel suite bedroom. Baekhyun had said the exact same words to him then. He gritted his teeth, but it was too late. Tears flooded his eyes, too big and fast for him to be able to stop them falling. He turned his face away, but knew he had failed to hide by the wordless noise of dismay Seulgi made. She put her coffee down and leaned over to wrap both arms around him.

“It’s okay,” she told him as he fought desperately with his tears. “It’s okay to cry.”

“Sorry,” he choked out.

“Don’t be. You’ve been through a lot.”

“We all have,” Chanyeol whispered. He closed his eyes to try and stop the flood, but the tears kept on leaking out despite his best efforts.

“Yes, but he was special to you,” Seulgi said. She didn’t say anything more, but kept her arms around him, patting his back in a slow rhythm. It should have been embarrassing to cry in front of his junior officer, but Chanyeol was all filled with grief, and there was no space left for shame.

He’d just managed to wrestle a semblance of control back when the doors to the operating rooms slid open and the surgeon came out. Chanyeol wiped his face on his sleeve hurriedly and stood up. The surgeon told them Sehun’s surgery had gone well and that he would be in the recovery room for the next hour or so. Chanyeol exhaled, and Seulgi nodded.

“I called his parents earlier,” she told Chanyeol. “They live out of town, but they’ll be here soon.”

Another thing he should have done as squad leader and forgotten. He cursed himself silently.

“I’ll stay and explain what happened,” Seulgi said. “You go home and get some rest.”

“I should stay -” Chanyeol started, but Seulgi had her don’t-mess-with-me face on.

“You should rest,” she repeated firmly. “Sehun’s parents don’t need to see you like this.”

He supposed she was right. The way he looked, they’d probably think their son was at death’s door.

He took the SUV with the intention of driving back to his apartment - a half-forgotten place he hadn’t been in days - but partway there he realised he’d taken the wrong exit. He was driving towards the apartment Baekhyun and Seungwan had shared. He briefly considered getting back on the freeway, but it felt like too much effort.

He pulled the SUV up outside the apartment building and got out. Seungwan had given him the door code so they could use the place as a meeting point between undercover agent and handler, although they hadn’t actually done this yet. He wasn’t sure if coming here was a good idea, but he was exhausted and lonely, and he wanted to be close to the memories of Baekhyun that were left in the place he’d lived.

He flicked on the light as he entered. It looked no different to the last time he’d been there. The apartment itself was small, a combined kitchen and living area with two tiny bedrooms leading off it and an even tinier bathroom, but it had ten times the character of Chanyeol’s bigger, more elegant place. The two orphans had taken the first space they’d ever had to themselves and made it theirs. The furniture was messy and eclectic, bright rugs and patterned blankets and mismatched cushions everywhere. The walls were covered in taekwondo posters and printed photographs, many of them of Seungwan and Baekhyun. Chanyeol stopped in front of one haphazard collection of photos and a tiny smile touched his lips. Baekhyun had both arms wrapped around Seungwan, who was holding a yellow belt in one hand and a certificate in the other, and both of them were beaming at the camera. Beneath it, Baekhyun had scrawled, Seungwan’s first grading - DISTINCTION PASS!!! This photo would be three years old, just after Baekhyun had brought his little sister out of the orphanage, around the same time he’d become Chanyeol’s partner.

He lingered in front of the photo wall. Seeing Seungwan in them, so bright and happy, made him think guiltily of the misunderstandings that had grown between them. He needed to do something about that. He’d been letting his grief and rage drive him, and he hadn’t had space left to think about anyone else. But that was unfair to Seungwan, who was doing such a dangerous and difficult thing.

Had he done the wrong thing in letting her go undercover? It wasn’t the first time he’d wondered this. She’d wanted to do it, and Chief Park had agreed, and he couldn’t deny that she’d done extremely well so far - but the longer it went on, and the more his grief wore from agonising sharpness to permanent, dull ache, the more uneasy he felt. In his dreams, Baekhyun still whispered to him. The words were always the same. Not my baby sister. Don’t involve her in that world. All I want is for Seungwan to be safe.

“I’ll catch him, Baekhyun.” The sound of his own voice startled him. He hadn’t meant to speak aloud. “I promised. I’ll find Chen and make him pay for what he did.”

Usually these words were filled with burning conviction, but tonight...tonight they echoed, strangely hollow.

He shook his head. The sooner he caught Chen, the sooner he could get Seungwan out of harm's way. That was the only way forward.

He went over to sit at the computer desk, intending to log in to the work server and check his emails before crashing on the couch. When he turned the computer on, a blue screen asked him to enter a password. He pulled open the large drawers under the desk, hoping Baekhyun or Seungwan might have written the password down somewhere. When he opened the second drawer, the label on a thick official file with the police logo stamped on it caught his eye.

At first he thought he must have misread it. His eyes went over the words again, trying to make them fit into what he knew of the world. The black handwritten letters bled into his brain like ink into tissue paper. Baekhyun had labelled the file Investigation on Park Seungjin.

Chanyeol lifted the file out of the drawer, pushed the keyboard aside and placed it down in front of him. He stared at it. He didn’t understand. No, he didn’t want to understand. But he had to understand.

He opened the file and started to read. Some of the files were typed, some were copies of transactions, records and transcripted phone conversations, some were notes jotted in Baekhyun’s handwriting. Chanyeol sank into the case, and the deeper he sank, the more he understood. Each leap of understanding was like a punch in the gut.

Baekhyun had been investigating his father for corruption.

He went to the back of the file for the earliest documents. He found the date on one of them. Three years ago. Right when he and Baekhyun had become partners.

He flicked back through the file. There was a lot of evidence here. Baekhyun must have been close to presenting the case. Taking down such a high-ranking official as the Chief of Criminal Justice would need a rock-solid case. No wonder it had taken him three years. The whole time they’d been working together…

It felt like a cavern opened up inside him. All that time, Baekhyun had been secretly investigating his father. He didn’t know whether he was more horrified by the fact that his father was under investigation, or that Baekhyun was the one doing the investigating. Was that why they’d gotten so close? The question scraped him like sharp nails. All they’d done together, all they’d shared...was it all just Baekhyun trying to get an inside view into Chanyeol’s family?

No. He shook his head. No. Baekhyun wasn’t like that. If he’d