I'm not going to lose her again.

Castle: They're going to kill you Kate, and if you don't care about that, please think about how that's going to affect the people who love you. You really want to put your dad through that? What about Josh?
Beckett: And what about you Rick?
Castle: Well of course I don't want anything to happen to you. I'm your partner, I'm your friend.
Beckett: Is that what we are?
Castle: You know what? I don't know what we are. We kiss and then we never talk about it. We nearly die frozen in each others arms, but we never talk about it. So no, I got no clue what we are. I know I don't want to see you throw your life away.

Don't leave me, please. Stay with me. Ok. Kate, I love you. I Love you Kate.

I know you crawled inside your mother's murder and didn't come out.

Just because you're smart and beautiful doesn't mean you have good judgement.

Relationships aren't math problems. You don't solve them by being practical.

Castle: What was your talent?
Martha: The way I wore a sweater.

How come I didn't hear about this on TMZ?

Death of a beauty queen. Scandalous.

You know what I thought when I first met you? You were a mystery I was never going to solve.

Castle: This is so weird, I dressed up as him for Halloween.
Beckett: I did too.

Castle: Worried you can't control yourself when we're alone?
Beckett: It's not me that I'm worried about.

Castle Quotes

Sometimes the hardest things in life are the things most worth doing.

Castle

Castle: You're not alone in this. I'm here.
Beckett: I know.