Author's Note: Thank you all so much for the support on this fic so far! I'm having a lot of fun with this, mostly because this is the first fic where I really get to dig into Castle a bit. So many of my other fics focus on Kate; she'll have her own part here as well, but this one's a lot meatier on the Castle side of things. Enjoy!

Somewhere Near D.C…

"This doesn't make any sense," Special Agent Tony DiNozzo muttered with a shake of his head as he placed a stack of papers back onto the wooden desk. For the most part, Herman Bass' apartment was nondescript, small with walls barely decorated with posters of bikini-clad models. "I don't even know what to look for."

"Meredith said he was her supplier," Ziva David offered, crouching beside the bed and shining a flashlight underneath the mattress. She grimaced when she didn't find anything. "Perhaps we would luck out and find his supply here."

"No such luck," DiNozzo said, taking a peek out the window and looking four stories down.

"This is like… finding a knife in a haystack."

"Needle," DiNozzo corrected. "It's needle in a haystack."

"Point is," Ziva countered, "we have yet to find anything to substantiate that woman's claim."

"Well, it's not a total loss." DiNozzo turned away from the window, crossing the small space between the bed and the bathroom, flipping on the light and dropping into a crouch to open the cabinets underneath the sink. The wood was faded and splintered. "It gets us away from all the tension."

"Gibbs has not been quite himself since we brought Meredith in."

DiNozzo squinted, his own flashlight illuminating the corners of the cabinet. "Well, you know Gibbs and redheads. A veritable Molotov cocktail if ever there was one. I'm kinda curious to see what the mystery writer has to do with all this."

"Have you seen his fiancée?" Ziva crouched beside DiNozzo, running the palm of her latex-covered hand along the side panel of the cabinet. "She is very pretty. Almost makes up for that awful name."

DiNozzo frowned. "What's wrong with Kate Beckett?"

Ziva frowned in return. "I thought her name was Nikki Heat."

DiNozzo smirked, pressing his palm against the other side of the wood paneling, feeling an inconsistency in the wood. Shining a flashlight on the offending spot, he noticed what appeared to be a secret compartment etched into the wood. "No, that's the character he's based on her. You can ask McGee all about it when we get back. But look at this."

Ziva inched herself closer to DiNozzo, her chin inches from resting on his shoulder as her dark eyes trained over the spot he was illuminating with his flashlight. She had to block out the scent of DiNozzo's aftershave, going so far as to hold her breath because sometimes the smell was intoxicating enough to distract her.

She fought the urge to bite her lip, especially when she noticed DiNozzo looking over his shoulder at her. She expected a smirk and a quip, but his eyes were as serious as she had seen that day.

"Secret compartment," she said to his nod.

"What do you wanna bet whatever Bass was supplying Meredith with is in here?" DiNozzo theorized as his palm pressed flat against the wood. He added pressure with his fingertips before a soft click accompanied the sensation of the wood giving way. By the time DiNozzo removed his hand, the wood panel flipped open to reveal several prescription bottles.

DiNozzo reached for one and squinted at the information printed on the label. "Modafinil."

Ziva frowned. "Sleeping pills?"

"The exact opposite," DiNozzo said, pulling an evidence bag out of the pouch of his navy blue NCIS windbreaker and placing the bottles into it. "They're for alertness, usually given to patients with narcolepsy. The drug itself isn't illegal, but I would imagine Uncle Sam would frown upon Bass selling them himself."

"And that is assuming the pills themselves were not modified in any way."

"That," DiNozzo said, rising back to his feet and trying to ignore the pop in his knee, "would be a job for Ms. Scuito."

NCIS Headquarters, Quantico…

By the time Kate Beckett finally found her fiancée, she saw him sitting in the break room - which wasn't quite as orange as the rest of the facility - hunched over one of the tables along the far wall and staring at the can of Coke in front of him. His posture alone was enough to tug at Kate's heart strings, and she found herself closing the distance before she even decided to.

He flinched ever so briefly when her hand came to rest on the space between his shoulders, but Castle relaxed when he saw who was touching him. He tried to match the small smile Kate gave him as she sat next to him, but it looked more like a grimace. His eyes were dark, and Castle had to close his eyes when Kate's fingers slipped in between his.

Kate opened her mouth to speak, but nothing came out. It suddenly occurred to her that she didn't know what to say. Asking how he was seemed stupid, and she felt lame offering little more than an I'm sorry.

She was hoping he would talk for her, like he so often did.

"Alexis was still a baby," Castle said, his voice low and cracking. "The day I walked in on Meredith with another man."

Kate blinked, taken aback by how frank the confession was. Meredith hadn't said a word about that the last time they had spoken, when Kate had asked her why things with Castle never worked out. Meredith had been a sporadic and short-lived part of their lives, only showing up in short bursts, disturbing things in her own unique way before flying off to wherever.

And in the aftermath, Castle had never said much about her. Occasionally, Kate would get the sense that he resented how little Meredith had been there for Alexis, but over the years, Kate had chalked up the demise of that relationship to how young and impulsive they both had been.

Castle had somewhat outgrown his impulsiveness - or at least, he had learned to hone it. Meredith, it appeared to Kate from the outside, never had.

Kate gave Castle's hand a squeeze. "How come you never told me she cheated on you?"

Castle shrugged and kept his gaze on the soda can. "Never really came up."

"I asked her once," Kate admitted. "Why the two of you didn't work out."

Castle's eyes finally rose to meet Kate's, lines of confusion forming on his forehead. His eyes were still far darker than usual, though they had lightened a little. "And I'm guessing that part never came up."

Kate shook her head. "She said it was because you knew everything about her, but that every time she tried to dig a little deeper into you, you kept her at arm's length."

Already angry, Castle felt a wave of it washing over him again - only to feel it fade when Kate's hand squeezed his. They locked eyes again and Castle sighed, his shoulders slumping. He pushed the can of Coke aside and leaned in closer to his fiancée.

"Look, I know I'm flippant and borderline crass sometimes," he said. "Humor has always been my coping mechanism, and sometimes I have a hard time turning that off. But if there's one thing following you around these last few years has taught me… nothing ever happens in a vacuum, Kate. A murder… it doesn't just ruin the victim's life, or the family or friends. It…" He shrugged and pursed his lips. "It's not just the fact that someone's dead, either. Secrets come out. People already grieving with loss are faced with the terrifying notion that the people they loved might not have been who they thought."

The anger was seeping back into Castle's voice as he spoke. Kate ran a soothing palm over the back of his hand, struck by how infrequently she had seen this side of him over the years. Then again, even the most personal of cases had never gotten to him quite like this one. Neither one of them had ever met Herman Bass, but his death had sent so many things spiraling out of control - not the least of which were her fiancé's emotions.

To say nothing of the lead agent working the case.

"As angry as I am right now," Castle admitted, "as hurt as I feel over the fact that Meredith isn't really Meredith… I can't help but feel even worse for Agent Gibbs."

Oh, Castle…

Even in the midst of his own turmoil, Castle was still thinking about someone else. Someone he had never met before until a few hours ago. His capacity of empathy had always been impressive - even when Kate was convinced he was little more than a playboy debutante stalking her under the guise of "research." But for him to be thinking of someone else right now… Kate couldn't help the small smile tickling her lips.

"To go that long thinking your wife and daughter are dead…" Castle shook his head. "I can only imagine the lengths Agent Gibbs would've gone to make sure whoever killed them paid."

Kate nodded in understanding. "He seems pretty relentless as an agent."

"Not Gibbs the agent," Castle corrected. "I'm talking Gibbs the husband and father."

Director Vance's office…

Even as he pushed through the door to Leon Vance's office, Agent Gibbs knew exactly what the conversation was going to be. It was the same every time a case came up that had a personal connection to a member of his team - and the fact that this was a case that harkened back to him made the coming talk even more obvious.

Gibbs shut the door behind him, coffee cup in his hand. But the contents were likely lukewarm by this point; since the conversation with the redheaded woman, the mystery writer, and his fiancé, Gibbs hadn't trusted his stomach enough to ingest anything.

Even the update Agents DiNozzo and David had given about the drugs found in Bass' apartment had largely fallen on deaf ears. Gibbs' team was smart and efficient; they could handle this one on their own if need be.

But that didn't mean Gibbs would back away.

"Agent Gibbs," Vance greeted, straightening his tie as he hung up the phone.

"Leon," Gibbs greeted in return.

Gibbs set his coffee cup on Vance's desk with an arched brow. Vance, leaning back in his swivel chair, clasped his hands together over his midsection and studied the cup before lifting his gaze back to his senior agent. "I understand you have a personal connection to this case."

Gibbs smirked and fought the urge to roll his eyes. "Would you believe me if I told you it was classified?"

"Considering the phone call I just received from the Attorney General's office?" Vance arched a brow of his own before pushing himself out of his chair and crossing over to the meeting table. "I'm well aware of the fact that Meredith Harper is a cover identity, Agent Gibbs. I'm also aware of her real identity."

Gibbs shrugged again. "This the part where you take me off the case?"

"I should." Vance slipped his hands into his pockets. "But I won't. I know you, Leroy. Taking you off this case is the most surefire way to send you head-on into it."

"Then why am I here?"

"Because you don't know the whole story." Vance grabbed the remote sitting on the conference table, turning on the flatscreen monitor. Front-and-center was a head shot of the redhead who now called herself Meredith Harper, along with a head shot of Herman Bass in front of an American flag.

"What she told you is correct; Meredith Harper is the identity Shannon Gibbs was given when she was placed into protective custody. Tracking down Kelly is proving even more difficult, because she was a minor at the time she was placed into the program."

"What about Bass?"

"I'm leaving that part to Agents DiNozzo and David," Vance explained. "Now, this… Jackson Hunt she told you about? We can't find him in any of our systems. It's likely that it's an alias. But, a contact of mine at the CIA told me there were rumblings of a Jackson Hunt in Paris several months ago."

Gibbs watched as the screen changed, revealing the head shot of another redhead. This one was younger than Meredith, probably no older than her early twenties. "This woman had been kidnapped by a Russian terrorist. Word is, Hunt was instrumental in getting her back."

"We know who she is?"

"Her name is Alexis Castle," Vance explained.

The recognition was instant, and Gibbs pursed his lips. He reached back for the cup on Vance's desk, taking a swig even as he wished there was something stronger than coffee in it. If ever a case called for a flask of scotch, this was it.

"Richard Castle's daughter," Gibbs posited.

"Could be a coincidence," Vance said, though the tone of his voice made it clear he didn't believe it was. "Nevertheless, I need to know what Richard Castle knows about this… Jackson Hunt."

"Ask him yourself," Gibbs said with a shrug. "He's here, along with his fiancée."

Vance didn't respond to that, but the straightening of his posture and the ever-so-slight way he tightened his grip on the remote told Gibbs that Vance knew something he wasn't sharing. Pushing was tempting, but would ultimately prove fruitless - Leon Vance never shared information unless he wanted to - but Gibbs had to admit, at least to himself, that his curiosity was piqued.

"Bring him in, then." Vance set down the remote. "Oh, and Gibbs?"

Gibbs stopped at the door. "Yeah, Leon?"

"Be careful."

Gibbs gave one of his patented half-smirks before leaving Vance's office and shutting the door behind him. Vance walked back over to his desk, his eyes still trained on the door as he picked up the phone and dialed a number.

The call connected on the second ring.

"This is Director Vance. I need everything you have on Kate Beckett."