What's a fiance for if not to find her future wife's current husband?

Castle: You should know it, you're engaged to a genius.
Beckett: Yes, a genius at annoying me.

Beckett: Tell me this is still part of the fairy tale.
Castle: If it is, it's a Grimm one.

You can't give up. That's the deal. We want the happy ending, we can't give up.

Castle: A crime scene at a fire. I've never done one of these before.
Ryan: After this you might not want to.

Ryan: Rather than pick a name for my kid you should pick a date for your wedding.
Castle: Pick a date for my wedding? I was planning on bringing her.
Beckett: Really. When is that? I might have plans.

Can we canvas the area? And by we I mean obviously somebody else.

Castle: The killer can't be a ballet dancer because it'd just be such a huge let down.
Beckett: Of course, we can't let facts get in the way of a good story.

If this is a tea company, I'd like a cup.

Lipstick marks on my shirt? Where? Beckett will kill me.

Castle: How about we have a winter wedding?
Beckett: Didn't we say we wanted to do it outside?
Castle: Oh, right. Frostbite isn't very festive.

Martha: A little unsolicited advice.
Castle: Do you give another kind?

Castle Quotes

This isn't one of your books, Castle!

Kate

Kate: Are you here to annoy me?
Castle: I'm here for the story.