Grimm Rings in the Holidays with Gators and Evil Santa!

'Tis the season for giving, and Grimm is giving double this year.
NBC's fantasy crime procedural will air two back-to-back episodes Friday at 9/8c, featuring Wesen that will put an extra chill in your winter. To kick off the night, the Portland PD investigates a string of murders that lead them to think that there may be something to that alligator in the sewers urban legend. "Wu has some ideas as to what's going on in the sewers," star David Giuntoli tells TVGuide.com. "Wu (Reggie Lee) has always heard that they've come up through the toilets I believe. And he was always afraid to have a bowel movement as a boy. And to that, I gave him a look that should read, 'Oh, Wu!' He's never had a bowel movement. That's why he's so uptight. He's trying to work it out, poor guy. Season 4 is just us giving Wu a barium enema the entire season."
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All kidding aside, Grimm's second hour makes Christmas creepy with the anti-Santa Claus known as Krampus. According to folklore and this Anthony Bourdain short, Krampus targets naughty children and carries them off in his sack. "He steals the kids and beats them with a switch, which is a branch," Giuntoli explains. "And the most bad of the bad kids get eaten at midnight. That's Grimm! A little Caucasian boy for dinner? Delicious!"
Check out what else Giuntoli has to say about guest star Alexis Denisof, Krampus and meeting Monroe's parents:
To fight off the gator Wesen, you get to raid Aunt Marie's trailer of goodies again!
David Giuntoli: Yes, it's always fun to get to use a new weapon. I can't remember the name of it. Nick is thrilled to be playing with this particular weapon. It's one of those that satisfies the boy in any actor. And there's a button I can press, and a blade would shoot out. It was very fun. This is like varsity level weaponry.
In this episode, we finally get to meet Alexis Denisof, who guest-stars as Prince Viktor Albert Wilhelm George Beckendorf. In a previous interview, Sasha Roiz said Vicktor would be the new Big Bad. How evil is he on a scale from 1 to Schnietmache?
Giuntoli: He's bad. He's out-Schnietmached the Schnietmache. He's worse. He's darker than a Schnietmache, an evil, evil man.
Will Nick & Co. get to Europe also and run into Viktor?
Giuntoli: There's a lot going on in the home front. I'm sure we'll meet him at some point. He's going to be our Big Bad. There's a throwdown. I have not yet worked with [Denisof] though I've met him on set. He's a great actor and a great guy.
Moving on to the next episode, this one is all about that evil Santa, Krampus. How did it feel to go up against him?
Giuntoli: That guy was crazy-looking. Rarely do I have a visceral, negative response to seeing another human being. But I did with Krampus. The horns. You know what he looked like? He looked like a character from Beetlejuice, which is just a little off of center. It's such a joyous childhood character, and we bastardize him and really ruin Christmas for everybody.
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What's your favorite thing about this holiday special, if we can call it that?
Giuntoli: Oh boy. I love whenever we get to see Bud (Danny Bruno). And we see Bud in this one. He's like this innocent, child's heart wrapped up in a refrigerator repairman's body. And he was terrified of Krampus when we discover where he may be keeping the kids. I love getting to work with Bud and also it usually means that there's a bigger party scene going on where a lot of the characters are together. It's one of my favorite things.
Despite all of this action, lurking in the background is Nick's ashen, going-dead thing still happening. How much more will we see?
Giuntoli: I don't know how much more we'll learn about it. That said, it's going to come in handy. My heart almost stops, so whatever practical use there is there. It helps underwater when trying to help a mermaid. It also sends me kind of to this zone, which I think is a kind of darker place. And I think it's good for Nick to have access to a darker place. It gives him permission to act a certain way that's not the way he should be acting, in an un-Grimm-like way.
Did you shoot the episode yet when Monroe's parents (Dee Wallace, Chris Mulkey) are in town? Does meeting them give any insight into how Monroe is, the way he is?
Giuntoli: Yes, we have filmed a couple of those episodes. I don't want to say too much. I wasn't around for a lot of those scenes, but I was for plenty of others. You definitely see where the conflict comes from. Never forget that what Monroe and I are doing, this new arrangement, is brand new. It's like Modern Family. This isn't how it's ever been done. A Fuchsbau and a Blutbad first of all living together is a big deal. But a Grimm coming to dinner at your house? Unacceptable. If my ancestors heard about this -- well, they have. My mother has seen this. It's not a normal thing. Frowned upon. It really is Modern Family gone dark.
There's an upcoming episode coming in the second half of the season titled "The Wild Hunt." Is it safe to say there's a lot of action?
Giuntoli: Oh my God. We just filmed on Friday night the finale of that episode, and it was a 15-hour fight. From 4:30 p.m. to 6 a.m. So it was a big, big fight scene, including an appearance from Monroe's parents.
Check out a sneak peek of the two-hour fall finale:

Grimm airs Friday at 9/8c on NBC.