A/N: Hello friends! I'm back. This chapter is about Probable Cause and I think, also my longest chapter so far! I wanted to write something different so I thought, hey, let's add Lanie to this mix. I'm not sure this turned out like I planned, but I hope you guys like it! Please leave a review either way. Happy reading!

'Beckett... They've been having an affair.'

As soon as those words register in my mind, I mumble an excuse, my eyes never leaving the file in my hands, yet never reading a word on the page, and run out of the room. Once I reach the break room, I finally stop to breathe. My mind feels like a beehive. Million things are buzzing around in my head, creating a mess I cannot make any sense of.

Is this really possible? Is all of what I've been told today true? Is it possible to be this wrong about someone you've known for over 4 years?

Who am I supposed to believe here? The evidence? My trained detective friends? My boyfriend?

Is Castle really capable of something like this?

I'd been so sure of it. I still refuse to believe it. But as much as I want to appear stronger than anyone else, I'm insecure. These emails? I don't want to believe that they're real. I want to be sure of it. But how can I be? Why would he settle for me? Of all the women in New York? Is it possible that he'd play me like this? Is it possible that my appeal was the fact that I told him no in the beginning? Was it the chase? And now that I finally gave into him, he immediately got bored?

I cover my face with my hands and sigh. Just a few days ago, I had been happier than in years. Now everything seems messier and crazier than ever before. One thing I know for sure; I have got to get out of here. I can't look at one more piece of crushing evidence against Castle until I get my head out straight.

I walk to my desk, throw the file on it, grab my jacket and speed walk to the elevator. I can't handle any more of Ryan's pitiful looks. I need to get away from here. From the murder board that currently supports a young woman's bloody face and my partner's headshot with the word 'suspect' above it.

I push the button and lean my head against the elevator's back wall and close my eyes. I can feel hot tears burning behind my eyelids. Once I reach my car, the first tears have already fallen onto my cheeks.

What am I suppose to do? Through everything, doing my job, and doing it well, has been so important to me. But as I've discovered, so is Castle. Even more important. I can't imagine him doing this.

Suddenly I open my eyes. He isn't. There is no way he's capable of doing this. I know my Castle, and he's not this.. He can't be.

I take my phone out of my jacket pocket. I need to talk this out. I need to say these things out loud and have someone listen to me or I will drive myself crazy. I need my best friend.

I send Lanie a text, asking her to come over to my place because I need to talk. She responds almost immediately, promising to come and bring a bottle of wine with her.

The whole drive home, I try to not think about the case, about Castle in holding.. Which results into me spacing out at a red light until someone honks in the line behind me.

Once I let myself into my apartment, it all washes over me again. Somehow, being home makes it worse. At the precinct I could put everything into doing my job, turn on the cop mode. But being home, where I'd spend many evenings and mornings with Castle, who is currently accused of murder, just feels wrong. Home is supposed to feel soothing and safe, but I just feel like something's missing. And I know very well what that is.

Suddenly there's a knock on the door. I glance at the clock. It's been 15 minutes. I'd lost the track of time yet again.

Wiping my eyes on my shirt sleeve, I make my way to the door and pull it open. Lanie's smile fades the second she sees me and she lowers the bottle of wine she was holding at eye level to her side.

'Oh sweetie..' She whispers and I start sobbing again. She wraps me into a hug and closes the door behind us. After trying so hard not to break down in front of the boys, it feels good to have someone comfort me, as hard it is for me to admit to needing someone.

'Let's go sit down, okay sweetie? And you can tell me everything.' Lanie says while rubbing my back. I nod against her shoulder and she lets me go, but not completely, still keeping her hand on my back as we make our way to the living room. I take a seat in front of my couch instead of on it, and Lanie follows my example, sitting on the floor across from me. She gives me a look that seems to suggest that I can start talking whenever I'm ready. I take a few deep breaths and try to will the tears to stop rolling onto my face. Once I've calmed down a little, I start.

'There's… New evidence that… Really doesn't look good, for Castle.' I manage to get out.

'Oh…' Lanie sighs. 'What is it?'

I try to think of a way to tell her, before I realize something. Lanie doesn't know about Castle and I. How did I forget that fact?

'Uh, well… They found a deleted file on his computer, where he wrote a story about committing the perfect murder that was… That was just like out crime scene.' I explain to her. 'And… According to some emails that they found… The boys think Castle was having an affair. With the victim.' I whisper at the verge of crying again.

Lanie is silent for a while, her brow furrowed. 'Is... Are they sure?'

I wipe my eyes on my sleeve again. 'I… The emails suggest so, yeah.'

'Wow… Uh, how did no one know about this? Not even his family?' Lanie asks.

'Because..' I whisper. 'Because he's in a relationship with someone else.'

Lanie's eyes widen in shock. 'Uh, so he cheated on her with the victim?'

I can only nod. Lanie looks shocked. 'Okay… God. And the girlfriend didn't know? Have you talked to her yet? Who is she? How did we not know about her?' She asks, her shocked expression slowly turning into an angry one. I can tell it's not quite as hard for her to believe the story as it is for me.

I take a deep breath before answering. 'Because we didn't want you to.' I whisper, again looking away from Lanie.

'What?' She asks, her voice full of confusion.

I make myself look at her. 'Because we wanted to keep it a secret. From Gates, because of the… NYPD dating policy, it… Made sense to not say anything to anyone at the precinct.' I reply, my voice almost disappearing completely at the end.

Lanie looks nothing but shocked. Her jaw is practically on the floor. I can't get any more words out so I just look at her. I see her expression go from shocked to angry to sad.

'Oh Kate…' She whispers, her eyes full of empathy. I lower my gaze again, not being able to see her feel so sorry for me.

'The day I got suspended, I uh, went to see him and… We talked things through. We… Agreed that we'd both screwed up but… We both wanted, uh, well… Each other.' I mumble an explanation.

Lanie sighs and I look up. She looks like she wants to ask me something but decides against it. In the light of how messed up the situation is, no normal relationship questions and friendly teasing is quite appropriate.

'So… Since when has he… Been emailing her?' She asks carefully. I'm quite thankful for her choice of words. As I start explaining, I can feel new tears burning my eyes and my voice breaks.

'They started up about eight weeks ago, according to those emails… He met her at… One of his books signings and… He asked her out for coffee and that was… It was just a couple of weeks after we started seeing each other.' I explain as my voice falters and I have to stop to take a breath.

'Oh sweetie…' Lanie says, her eyes glistening as well.

'He said he needed to keep it a secret because he was with someone else. And when he tried to break it off about a week ago, she threatened to go tell his girlfriend… And he offered to come over to her apartment to talk things through… And that was the night of the murder.'

Lanie looks at me for a moment, then gently says: 'He had a motive.'

I shake my head. That's not enough to label Rick as a killer.

Lanie sighs. 'What did Castle say when you talked to him?'

'He said the emails were faked. He said he never wrote that story, that he was being framed…' I try to swallow my tears. 'You should've seen him, Lanie, he looked like a little boy, he was so scared…'

Lanie only looks at me. Her eyes are filled with unshed tears, but I can't quite tell what she's thinking. Does she really think Castle's behind this?

'I know him, Lanie.' I whisper. 'He is… An immature, egotistical… Self-centered, Jackass sometimes, but he's not this.' I try to convince her.

She looks down for a moment before looking back at me with a sorry expression on her face. 'Are you sure?' she asks.

I stare at her, unsure of what to say. I look away and think.

As a cop, I've always been told to follow the evidence, to read them and build a case. To go with my 'cop gut.' But as Castle has thought me, that's not always enough. Is there enough evidence to make him look extremely guilty? Yes. Does he have an alibi? No. Do others believe he's capable of this? Apparently. But I've seen this happen before. Just as I think the case is clear, solved, something suddenly doesn't add up. And something doesn't add up here. This is Castle, we're talking about. Castle, who's mind has solved so many cases, helped so many people, saved so many people. Castle, who always knows to look for the story. Castle, who I've known for over four years. Castle who said he loves me. And no, he's not a killer. He wouldn't hurt someone else, especially not for what I know he would rule as his mistake. And he wouldn't make that kind of a mistake. I believe what I said to Lanie. I do know Castle. I've been wrong before, but not about him. Not since I saw that there was more to him than what's printed on page 6. I trust him with my life, why would I let this change that? No, my job is to find out the truth, and that's what I'm going to do. This is not over yet.

I look back at Lanie to give her an answer. 'Yes. I'm sure.'

After a long day of trying to convince Castle that Tyson is dead, we were finally sitting on his couch, warm and safe. I lay my head on his shoulder as he runs his fingers through my hair.

'Thank you.' I hear him say. I move my head so that I can look up at him.

'What for?'

'For believing in me. Even when I looked really bad.' He smiles warmly at me.

I smile back. 'Yeah well, there's been quite a few times where you've believed in me. Even if I was bad.'

He stares into my eyes, then leans to place a kiss on my forehead. 'You are most definitely good, Kate Beckett.' He whispers.

I'm just about to answer when I hear my phone beep a few times. I reach to grab it from the other side of the couch. There's three new text messages from Lanie.

'Heard about Tyson. I'm glad you're both okay.'

'AND that your boy is no longer a murder suspect! Yay!'

'Speaking of which; getting your freak on with the writer boy and not telling your best friend? You are in so much trouble Katherine Beckett! You owe me a girl talk and some expensive wine, girl!'

Please leave a review, I had to rewatch Probable Cause in order to write this and you know how painful that is? -S