Rick looks distressed when he tries to negotiate with an accused murderer on Castle. "Number One Fan" is the fourth episode of the show's sixth season.
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Things get serious when Rick tries to negotiate with an accused murderer on Castle. "Number One Fan" is the fourth episode of the show's sixth season.
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Rick ends up as the negotiator during a hostage situation on Castle. "Number One Fan" is the fourth episode of the show's sixth season.
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Castle Season 6 Episode 4 Quotes

Kate: I might as well apply to become a mall cop.
Castle: Ooh, you would look great on a Segway.

I don't know what to do about my life.

Kate