Disclaimer: Still not mine. Boo!

A/N: Pre-5x05 imagining based on the Promo. For BlueOrchid96. More angst than I normally write. You have been warned!


Improbable Cause

Chapter 1 - Breaking Down

"Kate."

There's such a look of absolute relief on his face when he answers the door to her that Kate allows him to draw her inside by the elbow and enfold her in an all-encompassing hug. But her body is stiff inside his embrace, rigid, and he pulls back after just a few seconds to look at her face when she steadfastly refuses to yield to him; to melt in his arms the way she always does now.

"Castle," she says, moving back a little and away from him, putting a modicum of space between them, her heart in her throat as his familiar scent engulfs her. "If Gates knew I was here…"

She leaves the rest of the statement hanging in the mid-air, unspoken, but writ large enough that they both know what she's saying.

"If Gates…?" he stares at her in disbelief, running a hand through his hair, unsettling its careful arrangement as he does so, wondering just how things got so bad, so serious for him, so damn fast.

"You're a suspect in a murder investigation, and I'm…I'm the detective of record, Castle," she needlessly reminds him.

Because, yeah, it's not like he'll forget this day in a long while.

"You might not be a cop, but you've been around long enough to know how that goes," she says, and he can tell from her posture, her rigid stance, and the set of her beautiful mouth just what this is costing her; holding herself back from him right now. Always the true professional.

She bites her lip, an adorable trait usually, he thinks, only now it's a sign of hesitancy and fear. And then she takes a deep breath.

"Castle, what do you want?" she asks finally, cutting her eyes up to meet his, exhaustion painting her face paler, sallower, than normal, her eyes and cheeks looking sunken; as hollowed out as her heart, as hollowed out as he feels.

"What do I…?" he asks, his tone disbelieving, eyes wide. "I want my girlfriend. My partner," he blurts, half angry, the other half just heartbreakingly desperate and so, so, terribly hurt.

"Castle, we have your fingerprints at the crime scene, and we have you on security camera buying jewelry for...for the victim," she chokes, her lips drawing into a thin pale line as she fights to hold it together.

Because this is so bad, so much worse than losing him to Gina that summer or…or watching him parade that stewardess, Jacinda, in front of her face. He did those things because she rejected him, because she lied to him and hurt him. But this…? She's given him everything she has, all of her now; her heart, her body, her…her future happiness… She was scared rigid when she held herself back from him, fearing that he might break her heart. But she battled through, realized she was so much poorer without him, and then they were together, and it was just so much more wonderful than she could ever have imagined. So close to perfect. But now…now the jinx that is her life, the curse that dogs her, is back to ruin her happiness and…

"Four years, Kate. Four years we've worked together, case after case, honoring the victims, side-by-side, hour on end. I thought that counted for something…I thought…"

She cuts him off.

"It did…does, but…"

She shakes her head, uncertain exactly what she wants to say, because this is a living, freaking nightmare.

"I thought you knew me, Kate, and, worse than that, I thought I knew you," he carries on, ignoring her use of the past tense, needing to get this off his chest because it's been brewing since she showed up at his home, a home he'd hoped to share with her some day, mob-handed, with uniforms for back-up and two of their best friends for…what? Support? Yeah, support while his so-called friends arrested him, took him in for questioning at the Precinct where he 'works', and then released him on his own recognizance pending further investigation.

"Four years I waited for you, Kate. Four years just for the chance to get to love you, to prove to you that I'm more than the man you saw when we first met. Do you really think I'm gonna throw all of that away, and for what?"

His voice is raised to a level she's only heard him use twice before. Twice before when her life was in peril and he was trying to save her. And now, in a strange kind of a way, she supposes it is again. The life she thought she had mapped out with him is crumbling into dust.

"I…I hold you in my arms and I watch you fall asleep at night. And…and I just feel so…so blessed. I love that your face is the first thing I see when I wake up in the morning, that I get to kiss you awake. It just brings be so much joy. You bring me so much joy. You mean everything to me, Kate. We mean everything…and yet…"

He looks exhausted, wrung out, when he palms his face, rubs his hand down over his eyes until his fingers rasp across the shadow coating his jaw, and she's not fairing much better. Her lip is trembling and there are fat tears blurring her vision, steadfastly refusing to fall, from the words that mean so much to her. Words she is desperate to hold onto, to draw inside of herself, to feed on, to nourish, to wash away this grain of doubt that's been germinating and sprouting all day.

"You know, when I asked you that first morning after you came to me…" he laughs, hollowly, "…funnily enough, begging forforgiveness," he says bitterly. "I asked if you were in this, and you said yes, it wasn't some kind of crisis thing for you. In case I didn't make myself quite clear that beautiful morning, I meant 'in this' as in, 'in sickness and in health, in this. As in, 'through bad times and good'. As in, 'til death do us part', Kate, until I could persuade you that it wasn't too soon to put a ring on your finger. That's how much this…us…means to me," he said, eyes shining fiercely.

"But the fingerprints? And…and the jewelry?" she chokes out on a sob, needing him to explain it away.

Because she loves him so much that if he can come up with anything half credible right now she'll grab it with both hands and hang on for dear life.

"I was buying it for you, Kate. You," he says, hating that he even has to explain this, and to her of all people.

"The fingerprint, I don't know, and how the necklace got to be there, I can only guess at this point. But I had that piece custom made for you. For our three month anniversary," he chokes, looking down at the floor and shaking his head gravely.

"Oh god."

Her hand flies to her mouth, and then the tears spill down her face as if on cue.

"Yes, oh god. Because you don't trust me, do you? You thought I did this. And how could you? You know me."

His voice rises again in anger and in pain.

"I'm sorry," she sobs, taking a step towards him, which he matches with his own step backwards; needing to maintain the distance between them right now. "I'm so sorry, Castle. I…oh god, this is such a mess. I didn't mean to come across as if I doubted you. Of course I know you could never murder anyone."

She says this, blinking all the while, as if the reality of it, the reality of what she's been holding onto - that he might actually be guilty - is now the most ridiculous thought she's ever entertained. As if his innocence was blatantly apparent all along.

"Do you? Do you really? Because you've been doing a pretty good job of looking like you don't trust a damn word I say," he snaps, pacing away from her across the living room floor and then rounding back towards her again, breathing heavily through his nose.

"I…"

She bites her lip, doesn't know what to say to fix this. "You're one of the kindest, gentlest, most generous people I've ever met…so, yes, of course there's no way you could have…"

"I think you should leave now."

The words are spoken so quietly, his tone so controlled - simmering anger dipped in the worst possible layer of hurt - that at first she thinks she's misheard him.

"I'm sorry?"

She's looking for clarity, for him to repeat himself so that she can be certain of the words she just heard him say. Instead she gets a cold, "Yes, you said that already. Now, please, Kate, just go."

"But, Castle?"

Her face is a mess, contorted with something akin to grief. Her eyes are wide, bloodshot and tear-stained, pupils dilated by panic that she's run out of time to fix this.

But he ignores all of that. Too tired to even argue anymore, he walks past her the few steps it takes to reach his own front door, and then he opens it quietly, without drama, and remains beside it until she turns around, walks towards him slowly, hoping all the while that there's been some terrible mistake, that he'll ask her to stay. That this isn't the end for them.

"Rick, please?" she says, as close to begging as she's ever gotten in her whole, adult life.

"I'll call you," he replies flatly, eyes not even meeting hers for a second, and as she wanders back out through his front door, numb as a zombie, the tears begin streaming down his face.

A/N: Oh dear. How could I? Yeah, well, I think I just did. Oops! Guess I'd better write another chapter to fix it? BlueOrchid96, you did ask… ;) Liv