Dean stares into the eyes of a canine in this photo. It is from the episode "Dog Dean Afternoon."
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A spell helps the boys communicate with a dog who witnessed a murder on Supernatural. "Dog Dean Afternoon" is the fifth episode of the show's ninth season.
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Supernatural Season 9 Episode 5 Quotes

All right, one more doggy pun and I'm gonna have your nuts clipped.

Dean

You know who wears sunglasses inside? Blind people. And douchebags.

Dean