Disclaimer: The only part of Castle that I own is the TV on which I watch the show.

Richard Castle has been known to evade the law, to scoff at it, to push it to the limit, but it has been a long time since he actually flouted it. He knows that he should feel guilty, should be wearing a hair shirt or performing some other equally unappealing sartorial act of contrition, but hell, he had a really good excuse. Truly. He swears.

It's not as though he broke into Beckett's mailbox and stole it. He knows that's a federal offense. It's more like a purloined letter. Oooh, good one, Rick, he thinks, giving himself a mental fist bump for his Edgar Allen Poe homage. He didn't really purloin it, anyway. More like appropriated it for a few minutes. And he put it back. She didn't even know. In fact, it's just one of a string of things she didn't and doesn't know. Not bad things, more like a string of magnificent pearls—at least, he hopes that's the way she'll think of it when she finds out.

They have been inching closer and closer to something for almost a year, and when they were sitting on the couch in their hotel suite in Los Angeles last week, they had come this close, this close, to winding up in the same bed. He had told her how amazed he was at the depths of her strength and her heart and her hotness, and she had said, "You're not so bad yourself, Castle," which was unquestionably the greatest compliment of his life. And they had locked eyes for a long time and then she had gotten spooked, excused herself and said goodnight.

Beckett may be the detective, but he has pretty good detective skills himself, not to mention spidey senses. Here's the first thing she doesn't know, the first pearl on the necklace: he knows that after she went to her room, she came back out just as he was going into his. He heard her door open and knew that she must have changed her mind. It took all his newly developed self-control not to turn around, run to the living room and pick her up in his arms. But he had realized, when she retreated, just how vulnerable she still was after the death of Mike Royce. And she still had a relationship with Josh Davidson, even if it was rocky and she hadn't seen him in months. If Castle had slept with her that night, she'd have been gone in the morning and every morning after.

Here's the second thing, the next pearl, that Beckett doesn't know. On the flight back to New York, he had been only half asleep when she was reading that letter from Royce. Through half-closed eyes, he had seen her reaction to it, every tiny twitch and frown and blink and stare and smile. He had seen that painful look of wistfulness, and he had left her alone. But later, when she was out cold and they were 36,000 feet over Kansas City, Castle had taken the letter from her seat pocket—see? it was in plain sight! plane sight! so what's the crime?— and read it. About him and Beckett having something real, about her fighting it and Royce wanting her to put her heart first for a change. And then he folded up the letter, along the deep creases that were evidence of how many times Beckett had read it, and put it back in her seat pocket. He had thought about it all the way home, while she was asleep. Now, five days later, he's still silently thanking Royce, at least once an hour.

The third thing Beckett doesn't know is that Castle overheard her break up with Josh, the evening after their return from L.A. Castle was partway home when he discovered that he'd left his phone on her desk, so he went back to the precinct. She wasn't at her desk, so he just scooped up his phone and decided to take the stairs rather than wait for the ancient elevator to make its way back up from the ground floor. He was walking down the 25-watt-bulb-lit corridor when he saw the two of them, right at the top step. Beckett's back was to him and Josh was so angry that he didn't even register that Castle was there. He crept away to the elevator, but not before he heard plenty, including Beckett's tearful accusation that Josh always put his job ahead of her and his recrimination that all she ever talked about was Castle.

He should be embarrassed about eavesdropping, chagrined that he's thrilled that Beckett talked about him a lot to Josh, but he's not. He's ecstatic. He's been in love with her for more than a year, and he'd bet his enormous Nikki Heat royalties that she's in love with him. Not that he can actually wager that money, since almost all of it is in trust for Beckett, which is another thing she doesn't know. Another pearl.

Beckett hasn't told him about the breakup, even though it happened four days ago, but he thinks that the flirting that they long ago elevated to an art form has gotten a little more, a little more something. Heated? Pointed? Open? Suggestive? Not in front of Esposito or Ryan or Montgomery or, God forbid, Lanie, but when it's just the two of them, sitting at her desk or driving to a crime scene. All of which led him to today. He stayed away from the precinct, his agnostic soul praying for no homicides in the vicinity of the Twelfth, to work on his plan for this evening, what he was going to tell her. He had texted Beckett that he had a meeting and asked if she'd like to grab something to eat at a new Indian place that had just opened inside the park. She had said yes (yes!) and that she'd meet him there.

He was ready way too early, but it's a beautiful late spring evening so he's walking there. He enters the park at Seventh Avenue, and heads for a path that runs along side some ball fields and a small playground that's tailored for little children. It's nearly eight now, so there are no kids playing there, but he notices some movement. He ignores it at first, until he catches sight of one his favorite colors, chestnut. Chestnut hair, his favorite hair, flying around the face of his favorite woman in the gloaming. (The gloaming? he asks himself. Oh, he's in deep.) It's Beckett, and she's in one of the swings. She's too tall for it, but she bends her legs and pushes herself off from the ground and thrusts those magnificent legs in front of her as she soars out and back with what he can only think of as abandon. She's uninhibited, almost reckless in how high she's pushing herself. He comes a little closer but stands in the shadow of a tree. He has never seen her like this before, really carefree, so exuberant. She's slowing down; she stops, and toes the dark padding that covers the area, but she stays on the swing. She looks contemplative now, and he comes up behind her, grabs the two chains of the adjoining swing and sits down on it, facing her.

"Hey, Beckett," he says quietly.

She starts. "Castle?" She smiles at him. "Oh, hi."

"Never would've taken you for a swinger."

"Yeah, well, um."

She's embarrassed. It's adorable. "Wanna swing with me?" he says, raising his eyebrows.

"Think you can you keep up?" Oh, yeah, flirting is underway.

"You bet your ass I can, Beckett," he says, pushing his feet hard for a spectacular take off.

Boom! His swing collapses, and his ass, not hers, is on the ground along with the rest of him. Beckett grabs the broken swing to keep it from hitting him, and kneels next to him.

"Castle! Rick? Are you all right?" She has one hand around his wrist and the other on his chest. "Can you breathe? Are you hurt?"

Oh, God, calling Botticelli, she looks like an angel. He'd thought he was destined for Hell, had sealed his fate when he took that letter, but here he is with an angel four inches away from his face and her hair tickling his neck, so this has to be Heaven. And now her hand is on his cheek and it's so soft. He's going to stay here forever, which is obvious, given that this is Paradise.

"Castle?"

The angel is talking to him again, and this time he's answering. "You're an angel. But angels aren't corporeal, and you're corporeal. You're very corporeal, Angel Beckett."

"What?"

"That swing broke and I fell on my ass. Thought I was dead. When you put your hand on my chest I was pretty sure I was in Heaven."

Beckett plunks down, laughing. "So you're okay?"

Castle manages to sit up and runs his hands over his head and chest as if checking for damage. "Yeah."

"Maybe it was that extra cannoli you had yesterday, Castle," she says, poking his stomach with a fingertip.

"You saying I'm fat, Beckett?" he says, wearing an expression of shock that wouldn't fool a five-year-old.

"Just more of you to love, Castle."

Oh, dear God, he's hearing Heavenly choirs. Choruses. Trumpets, harps. Did she really say that? Before she can retract it or brush it off, he takes her hand, and laces his fingers through hers. The expression that has come over his face now is shock of a different kind. "Love, Kate?"

Beckett figures she has two choices. Run like hell, or fess up. She chooses the latter, but she confesses very softly, and looks directly into his eyes while she does it. "Yes. Love."

After all this time, that's all it took. They kiss the way they had outside the warehouse a few months ago, only this time they don't stop, and this time they don't pretend it means nothing. Castle's pretty sure that they're not going to make it to the Indian restaurant. And he's more than sure that he's going to tell her all the things that she doesn't know he knows, and tomorrow he's going to buy her some pearls.

A/N This story was inspired by an S7 finale tweet from Nathan Fillion: "That swing broke and I fell on my ass!" Many thanks to temple01uk for forwarding it to me.