Castle and Beckett don spacesuits and enter a Mars simulation to figure out how an astronaut ended up dead on Castle. "The Wrong Stuff" is the 16th episode of the show's seventh season.
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We really hope that this is the last time Castle and Beckett will have to face off against 3XK.
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Can Castle and Beckett find a way to take down 3XK even though he's stolen all of the evidence they previously had against him?
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And before you know it Rick Castle's arch nemesis is back and it appears he's enjoying egging Castle and Beckett on once again.
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When clues to a murder point back to an old case, Castle finds himself back at the 12th precinct to consult.
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At least it looks as though Rick and Kate are working the case together, despite Castle being banned from the precinct.
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We know Rick can always count on Kate to have his back but what's so shocking that it put that look on her face?
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Rick enlists Kate's help when he witnesses his client's murder but has no evidence to prove her husband was the killer on Castle. "I, Witness" is the 13th episode of the show's seventh season.
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Castle Quotes

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

Back stabbing, adultery and betrayal. That is why I hate politics.

Kate Beckett