Castiel gives Bartholomew the Angel Eye during a discussion after he is captured in "Captives."
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Someone hands an interesting looking item to Bartholomew as Castiel looks on in "Captive," Season 9 Episode 14.
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Supernatural Season 9 Episode 14 Quotes

This is not happening. I spend months getting through the veil to listen to Dean Winchester having some pity session. I heard enough of those when I was alive.

Kevin

That's your third unanswered voicemail. Did you ever think maybe he's not that into you?

Sam