Exclusive Clip: 'Grimm' Scares Up Santa

When I sat down with Grimm star Dave Giuntoli at the start of the season there was one episode he couldn't wait for the fans to see: "Our Christmas episode is going to be insane! It's crazy. There's an actual evil Santa fable is out there that isn't that famous in America, and we do that. This big, fat white guy rolling into kids' room is not hard to spin that in a creepy way."

Well, the aforementioned episode airs this Friday and ETonline scored an exclusive clip from Twelve Days of Krampus.

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The gist of this particular legend is that our benevolent Santa Claus has a bizarro doppelganger named Krampus, who punishes kids on the "Naughty" list on Christmas Eve. Thankfully for the nation's misbehaving boys and girls, Nick is on the case! Watch!

Grimm airs Fridays at 9 p.m. on NBC.