I believe her exact words were, “Sure, maybe we'll get lucky and Castle will get shot.”

Esposito: So you're going full hipster now.
Ryan: Have you started jarring artisanal pickles yet?

You're supposed to be our buffer. Buff!

Castle, nothing you do is little.

Our witness is threatening to file a complaint against me for assault with a deadly odor. She says that I smell like soiled baby diapers and Javi's cologne is quote, "satan's butt sweat."

Kate Beckett: You texted Castle and not me?
Kevin Ryan: Well, when you have a crazy theory you don't call the voice of reason.

Then who's this, your evil twin?

The good news is Sarah Grace will have enough money for college. The bad news is she'll have no idea who I am.

Mars. Nova Scotia. This guy really loves barren landscapes.

Ryan: Do you think she's still alive?
Castle: She's alive.
Ryan: How do you know?
Castle: Because he's not done with me yet.

She might have been killed by a psychotic plumber lying in wait.

Castle: Ryan, you played the C card?
Ryan: You weren't around. Somebody had to step up.

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