Check out this sneak peek at the Castle episode "A Deadly Game." During this minute-plus scene, Castle and Beckett discover their victim was a spy of some kind.
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In this clip from the Castle season finale, the main character's writer friend speculate about his distracting relationship with Beckett. Watch and enjoy!
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On the season finale of Castle, Monet Mazur returns. She helps cause tension between Castle and Beckett, as the pair also investigate a murder.
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Castle Season 2 Episode 24 Quotes

Now we know why our victim doesn't exist... He is a spy.

Beckett

Castle: How old would you say that kid is?
Martha: Old enough to do all the things you did at his age.