This is a scene from "A Dish Best Served Cold." It is the third episode of Grimm Season 3.
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Nick and Hank end up investigating an old feud on Grimm. "A Dish Best Served Cold" is the third episode of the show's third season.
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Grimm Season 3 Episode 3 Quotes

And this little piggy went to jail.

Renard

Renard: Let me ask you something Nick: what’s really bothering you, the fact that you killed somebody or the fact that you killed somebody that wasn’t Wesen? Because God knows you killed plenty of them. That’s what you Grimms do, isn’t it?