This is what she dreamed of for a whole year.
She can stand at the whiteboard and not have him chattering on about magic and the mob and But Beckett what if the aliens looked like us and that's why he doesn't remember their ugly green faces. Her paperwork no longer gets turned into paper airplanes to be tossed across the precinct at Ryan and Esposito. The background of her computer is back to the NYPD logo, not Castle's smiling, cross-eyed face.
But now? Now it makes her miserable.
Finding his paperclip chains tangled up in her binder clips and pushpins causes her to frown. While searching for a working whiteboard marker in her desk, she comes across a notebook covered with his handwriting; bits of dialogue and funny doodles mixed in with actual notes on their cases.
Doesn't help that Josh broke up with her when she told him about just how she and Castle managed to save the rest of her team during the last case.
Even the boys have picked up on her mood change. Ryan brought her one of Jenny's cinnamon rolls this morning, insisting it was only because she wanted them out of the house before she ate them all. Esposito offered to cover dinner for them when it was her turn to spring for Thai.
"Hey, Ryan. Want to check who that $300 check was written out to? Maybe that'll lead us to someone who knows what-"
"Yeah, I think I can help with that."
She spins, already smiling when she finds him leaning against the metal divider. "Castle. What're you doing here?"
"Well, your victim is my client."
"Wait, what?" she asks, pushing back from her desk. "Your client?"
He digs in the pocket of his suit jacket, handing her a piece of folded paper as he rounds her to sit in his old chair. "I found myself with a lot of downtime recently so I got my private investigator's license. Zoey hired me the other day to find out if her husband was cheating on her. That's the $300 check."
For a moment, it feels normal again. Him in his chair, she in hers, the murder board covered with crime scene photos and her neat handwriting narrating the story.
"You're a P.I.?" exclaims Ryan, wheeling his chair over. "That's so cool!"
The two catch up but Kate can't stop looking at the license dated six days after Montgomery told him the district attorney thought he was too big a liability for the department. Six days after he went from kissing her in a dimly-lit alley to punching a hitman who tried to take her out.
Tangible proof that he doesn't just care about being her annoying, handsy, talkative shadow. He wants to be back.
"Zoey found my ad in the Times and called Tuesday. We met on Wednesday at my office," Castle explains, happily holding court once more. "She said she was concerned that her husband was pulling a lot of late nights at a job which had never required them in the past. I was going to start tailing the husband, Daniel, tomorrow afternoon but Zoey never showed up today to give me the address of his office."
"We didn't know about the cheating thing," Kate interjects. "If he found out that his wife was getting someone to follow him, even if you hadn't started yet, that might be motive to kill her."
He grins. "So I helped?"
Kate hands him the marker, nodding toward the whiteboard. "Want to add your insights to the board?"
Castle jumps up, hastily uncapping the marker and printing the cheating angle in careful capitals, well aware of how particular Kate is about the board.
"Mr. Castle, I don't think you're supposed to be here," Montgomery says, standing in the door of his office. "As much as we miss your presence around this place."
He drops the marker into the shallow well under the board, stepping away. "Captain, I was just-"
"He was helping, sir. He had a connection to our victim and just dropped by to inform us of another angle on motive," Kate jumps in, standing to defend Castle. "But he's leaving now. Promise."
Montgomery sighs, returning to his office.
They walk to the elevator, his license in her hands as he says goodbye to Ryan and Esposito.
"Sorry if I got you in trouble," he says, hands in his pockets as they wait for the elevator to hit their floor.
"No, Castle," she insists. "You helped us out but maybe next time call so we don't get the evil glare from Montgomery for encouraging you?"
"Think I can handle that. And hey, if you want to let me know how this all pans out or you need some professional insight, you can always stop in," he teases, handing over a business card.
Kate narrows her eyes, running her thumb along the edge of the cardstock. "You know we managed to solve crimes before you came along, right?"
"But you weren't having any fun, Beckett," Castle says as the elevator dings.
She gives him back the license when the doors open behind him, tucking his card into her blazer pocket. "If you say so. Now get out of here before I get my ass reamed for talking to you."
"Good luck," he wishes as he gets onto the elevator.
Even absent, he helps to close the case.
Once they book Daniel on the murder charges, she leaves the paperwork for tomorrow and takes the subway to the address on his card.
The place feels like something straight out of the 1940s with wrought-iron doors over the elevator and original glass in all of the windows. Figures he'd pick this building out of all the available leasing spaces in the city.
She knocks lightly on the door marked with a brass plaque, waiting to hear him call her in before pushing into the office.
"Beckett! Hey!" he exclaims.
Kate keeps her hands in her pockets, afraid that if they showed, he'd see how they shake as she looks around the office. "Not bad, Castle. Definitely a step up from the precinct."
"Still making it my own, you know," he says, following her gaze over the antique phones and piles of hard-boiled detective books along the windowsill. "Adding things here and there."
"Well, you fit." She closes the door behind her with a click, walking over to his desk, her fingertips trailing along the weathered wood. "Just thought I'd let you know that your lead closed our case. So, thank you."
"Lending my expertise to the NYPD is the least I can do," he boasts, leaning back in his chair.
"You know Montgomery didn't want you to leave, right?" Kate asks, propping her hip on the edge of his desk. "That the decision was made by the district attorney himself and there was nothing we could do to stop it."
"I understand. I mean, yeah, I'm disappointed that I can't hang out with you guys but I guess it makes sense. Can't have some civilian consultant beating your suspect to a pulp."
Beckett sighs, tilting her head to study him. His hand still looks stiff, the bruises faded to a pale yellow. "You did good," she whispers. "Saved my life. Again." She remembers his face when she finally got up and ran over to him, finding him kneeling over Lockwood with his hands bloodied and a terrifying mix of anger and fear in his eyes. "You're good at this, Rick. At finding the story within the evidence and getting it to make sense but why become a P.I.?"
He frowns, reaching out to nudge his glass of whisky a little further onto his blotter. "Because…" He pauses, rethinking his answer. "Because I like it. Because you taught me that life can be more than parties and meaningless flings. You showed me that I can do something that matters and I missed that the instant I left the Twelfth."
"So you were hoping you'd run into me?"
"A little, yes. But can you blame me? You showed me a better life and then I had it taken away," he explains.
Kate smiles, bolstering the same courage that pushes her to go through doors with her gun drawn. "What if I told you that you didn't need to go back to the 40s to cross paths with me?"
He has a moment to gasp "What?" before she balances a knee on the cushioned seat of his chair, a hand balancing on his shoulder as she touches her lips to his.
His hand curls into the thick wool of her coat, a low groan rumbling in his throat that makes her smile softly against his mouth. She smooths her thumb along his hairline behind his ear, nails scratching lightly at his scalp as he deepens the kiss until she breaks away, breathing with her lips resting on his cheek.
"You don't need a reason to find me in the city, Castle," she murmurs. "I'm right here and I'm not leaving. And I hope you feel the same way or this is going to be very awkward."
He pulls her supporting leg up so she straddles his lap. "You're in this?" he asks. "No matter what?"
"I'm not telling you it'll be easy but yes," she says, following the line of his scruffy day-old hair growth along his jaw. "Private eye and all."
Inspired in part by comments made on tumblr.