Castle is seen here with his daughter. On season three, he deals with the latter actually having a boyfriend.
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HA! HA! Castle gets laughed at, big time, in this scene from the 10/11/10 episode, "Punked."
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There's a reason Castle and Beckett look confused in this photo from the episode "Punked." The victim they are investigating was killed with a bullet that's 200 years old.
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Castle Season 3 Episode 4 Quotes

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

Just saying, he was probably very comfortable when he was shot and killed.

Castle

Castle Season 3 Episode 4 Music

  Song Artist
Alec ounsworth me and you watson Me and You, Watson Alec Ounsworth iTunes
Nitzer ebb kiss kiss bang bang Kiss Kiss Bang Bang Nitzer Ebb iTunes