Disclaimer: I own nothing.

A/N: This is just the prologue which begins in medias res. I promise other chapters will be longer. A million thanks go out to my twin soul Melissa for her brilliant beta work.

When the captain entered the bullpen with a grim expression on his face, Castle knew this couldn't be good news.

"Beckett," Montgomery called. He didn't meet her eyes, instead gesturing for her to follow with a careless wave of his hand.

Castle wanted to catch her gaze, but she averted her eyes. He tried to think of something encouraging to say, something like, I'm sure whatever it is doesn't have to do with you personally. Or, I'm sure that, on the off chance there is some evidence that somehow connects you to this case, it was a lab mistake and I will personally go down there myself to flog the idiot young-in who dared to accuse Detective Beckett of murder.

Or maybe just, whatever happens, I'm here for you.

Beckett closed the door behind her as she entered Montgomery's office. Through the blinds on the window, Castle, Ryan, and Esposito attempted to read the captain's lips.

"I got nothing," Esposito admitted. "Castle?"

"Hmm," he said thoughtfully. "Well, I don't consider myself an expert in the art of lip reading, but I think I can make out a few words."

"Like?"

Castle squinted in his effort to lip-read. "Your…ricochet…is…a…catch?"

Ryan and Esposito exchanged looks. Ryan rolled his eyes and turned back to his paperwork.

Castle frowned. While he couldn't make out the exact words, he could tell that Beckett was growing agitated by whatever Montgomery was saying. When the captain tried to lay a comforting hand on her shoulder, Beckett jerked away as if she'd been burned. She was shouting now, though her words were muffled by the wall. She gestured wildly, and her eyes burned with anger, and maybe – was he just imagining it? – fear.

Suddenly the captain's door flew open and Beckett stormed out. Castle quickly turned away from the window and pretended to be busy with something at his desk.

"Kate!" Montgomery emerged from his office. "Kate – wait!"

"Is that an order?" Beckett said icily.

"No, of course not, but-"

"Then I'm going home." She snatched up her jacket and a stack of case files from her desk. "I can't be on this case anymore, remember?"

"You can't leave." Montgomery caught her arm. Castle stood up, watching apprehensively. Beckett tried to pull away, but the captain tightened his grip. "No – no, listen to me, Kate," he hissed. "This is bad, but I can help you. I can't help you if you walk out that door." She shook her arm, but he still didn't release her.

"What's going on?" Castle asked.

"Stay out of this, Castle," Beckett snapped. "And you," she added to the captain, "let me go." She wrenched her arm from his grasp.

"Detective!" Montgomery barked as he tore after her. Castle hesitated for a fraction of a second before following them, Ryan and Esposito trailing close behind.

They caught up with her at the elevator bay where she was repeatedly jamming the down button. "Come on," she growled in frustration.

"Kate, please," Montgomery tried again. "I'm not ordering you, but I am asking you, as your superior officer and your friend, to just wait a minute. Don't walk out of here."

"You want me to stay?" she challenged. "Then arrest me."

Montgomery blinked. "You know I don't want to do that, Kate."

"And I don't want to stay." The elevator arrived at last and she stepped inside. It was empty. Just before the doors closed, Castle darted forward and followed her. He firmly pressed the doors open button.

"Tell me what's going on."

"Castle!" Beckett cried in exasperation. "If you don't—"

"Tell me what's going on," he insisted. "I can help you."

"Get – out – of – here," Beckett demanded. She began prying his hand that was holding the elevator doors open. "I'm going home. And I don't need help from you or anyone else."

"Please," Castle said weakly. "Please let me help you. Just tell me what's going on. I can protect you-"

"I don't need protection!" she snapped.

"Kate, I swear if you walk out of here," Montgomery began threateningly. He leaned closer and dropped his voice, "I know this looks bad. I don't know what to believe right now. But I know you. And I know that if you're innocent, you wouldn't be storming out of here right now."

She snorted in disbelief.

"Look," the captain tried again. "I want to help you, I do. No one thinks you did this, but if you leave now…I swear to God, Kate, everyone will think that you're guilty."

"Including you?"

He didn't answer directly. "Take the polygraph, Kate. If you're telling the truth-"

Her expression hardened. "If? Sounds like you've already made up your mind. And by the way, since when did we stop believing evidence? Since it started showing you what you didn't want to see? That's a load of crap."

"Evidence isn't everything," the captain said.

"It could be a lab mistake," Castle ventured.

Beckett laughed hollowly. "A lab mistake they checked three times? Face it, Castle. You're going to need a muse for Nikki, because my DNA was found at the scene of the crime."

Castle was stunned. "But – what – you?" He looked at Montgomery, who simply stared sadly at Beckett. Castle was so distracted by this news, he didn't feel his pressure on the button going slack, or Beckett's hands forcing him to relinquish the button at last.

"Now get out of here!" Beckett shouted at him as she bodily shoved him out of the elevator. Castle stumbled back into Montgomery as the doors slammed shut. He threw his weight against them, but it was futile.

Kate Beckett was gone.

A/N: Thanks for reading! I hope you enjoyed. Please review!