You know when I hung up my shingle as a P.I., I knew I'd have to follow some wives, I just never thought it would be my own.

Castle: The fact that you even think that breaks my heart. I would walk into a tornado for you, Kate.
Beckett: And I would die if I lost you.

Beckett, I think your crime scene's making a run for it.

Martha: I told you, if you can't tell your mother what you're doing you should not be doing it.
Castle: Yes, when I was eight.

You want to know what hurts the most? You could have come to me with everything. Broken us up just like you did only it would have been a cover and together, in secret we could have taken this guy down but that thought never even occurred to you because deep down inside you like being broken and you need this obsession and no matter what I do I can't change that, only you can, Kate.

Castle: Kate, I have never given up hope, not since the day we met and that will never change until you tell me it should.
Beckett: Then don't change, ever.

No relationship can survive secrets or lies.

Castle: They've been through way too much together to give up on what they have.
Beckett: You're a wise man Castle, with a big heart and you're rather good looking too.
Castle: You might want to pace yourself with the flattery. You've got a whole dinner to get through.

Martha: Is that the old friend who almost got you killed a few years ago?
Castle: Yeah, like six times.

This separation thing is getting really old.

Martha: Off, Off Broadway.
Richard: Mother, that was New Jersey.
Martha: Off, Off Broadway, as I said.

Here I am. Roguishly handsome and at your service. What do you need?

Castle Quotes

Castle: How do you know when you're in love?
Beckett: All the songs make sense.

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

Castle