A scene from “One Life to Lose”

Kate Beckett: Okay, found the deal memo Sarah signed in order to get Lance out for his movie.

Rick Castle: He wasn't lying. My mother's never going to let me forget this.

Kate Beckett: Oh, come on, Castle. She'll probably think it was sweet that you were concerned about her.

Rick Castle: This is Martha Rogers we are talking about. I intruded on her "moment." No, I will pay dearly.

Kate Beckett: When Lance came here, Sarah told him that someone wasn't who she thought they were. Who do you think that was?

Rick Castle: How about the woman who makes my mother look like a saint?

Kate Beckett: Yeah, but Sarah already cut Gloria out of her life. Maybe ... Maybe it was her cheating husband.

Rick Castle: Except Lance met with Sarah after Mandy Bronson. By the time Mandy showed up, Sarah'd already decided what she wanted to do with her marriage.

Kate Beckett: Yeah, but even if Sarah decided that she was gonna get back together with Vince, it doesn't mean that she didn't have doubts.

Rick Castle: No. No, you're right. Except he has an alibi. Everyone has an alibi.

Kate Beckett: Yeah, well, somebody out there doesn’t, and we are gonna find them.

Rick Castle: [looking at his watch] Maybe we should sleep on it. [Beckett looks at him] Separately. Katherine Beckett, I never…