Castle and Beckett come to a startling realization in this clip. Watch now to find out what it is.
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Castle thinks back to his life as a trouble student in this clip from "Smells Like Teen Spirit." Watch now.
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Castle and Beckett face the issue of a ... real-life Carrie on the episode "Smells Like Teen Spirit." Watch this clip now.
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Castle Season 6 forges ahead with "Smells Like Teen Spirit." Watch the official promo now.
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Castle Season 6 Episode 15 Quotes

Beckett: I'm not choosing our song off of a list that includes Def Leppard's "Pour Some Sugar on Me"
Castle: That song, I'm sure ignited many a strip club romance back in 1987.

I'd offer a theory but I'm too busy having detention flashbacks.

Castle