Tonight’s two-hour fall finale of Grimm is a shining example of what happens when some of TV’s most creative writers decide to pen a truly twisted and delightfully gruesome take on the holiday season. Beginning with “Cold Blooded” at 9PM on NBC and immediately followed by “Twelve Days of Krampus,” Grimm ends its fall run with significant character development and story advancement in one of their best (and most fun) episodes this season. Parade sat down with Monroe himself, Silas Weir Mitchell, to discuss the episodes, Krampus, where Grimm is headed when it returns, and who does the Christmas decorating in his house.

When you got the call in 2011 to essentially play a werewolf on Grimm, did you ever imagine you’d be donning sweaters and preparing vegan dinners?

It’s funny. The vegan thing was in the pilot script so I knew that they were working this angle of a guy straddling two realities or two ways of living. I knew it was going to be about this inner conflict, which is a really rich vein to mine as far as comedy and breadth of expression. I knew there would be a certain focusing on the cover for the darkness. As far as the wardrobe, the only thing that I said when I had my very first meeting with any wardrobe people (before we had even shot the pilot) was, “I think there’s a kind of avuncular, professorial quality to the character that fits the Portland fall and winter type of thing.” I was thinking of corduroy jackets with leather elbow patches. As far as the sweaters go, they just got into that thing and it’s funny because you see them everywhere now. Everyone has these big roll, shawl-collared sweaters.

How does the fan base for Grimm differ from the shows you worked on before?

Well, you can certainly tell the difference between a Prison Break fan and a Grimm fan. [Laughs] I love that there’s an ingenuousness about the Grimm fan. They want to go along for the ride because the concept of the show is outlandish. And, yet, what I think makes it fly is that it’s taken very seriously. Despite the sort of oddball comedy (of which Monroe provides a lot of), it has to be based in the situation and the character. It can’t be cute for cute’s sake. That’s just death. This guy I play that lives in Portland has to be very real, and then that stuff works. And same thing for the fans. They take it seriously, and then they have fun with it.

Silas Weir Mitchell in Grimm (Courtesy of NBC)

This fall finale is great and the Krampus story (“Twelve Days of Krampus”) is fantastic for the holiday season. There’s a moment that reminds me of Elf, when Rosalee opens the door and sees that you’ve decorated the entire house in the most elaborate way.

[Laughs] Right! It’s like, “How could any one man have possibly done this?”

The story that Rosalee tells, as well, is reminiscent of Gremlins. Do you guys look out for those kinds of Easter eggs throughout the season?

I don’t. I’m not a culture vulture, so I don’t pick that stuff up. It could be the writers because they’ve written in this genre before with Buffy the Vampire Slayer and Angel and so on, but I don’t pick it up.

The fans online pick every episode apart for stuff like that.

Oh my God. They look frame by frame. They’re very passionate.

Monroe is clearly an accomplished Christmas decorator. Do you handle the holiday decorating in your house?

No, my wife does. She particularly loves Halloween, so we have lots of fun with decorations. When we’re at home in Los Angeles, we get the whole Christmas tree and string up the lights and have the whole house smell like a pine tree. It’s fun.

What can you tell us about where Grimm is heading for the rest of the season?

Well, I only know a few episodes in advance, but there are a lot of threads. Juliette starts getting involved in helping Nick put it all back together. There’s the sickness from his zombification that has actually given him some extra powers in certain ways. There’s definitely a lot of royalty stuff going on. There’s a lot of haggling about the future of the relationship between Adelind and the Royals and the Captain. That’s a major thread. On my side of things, we get into some of Rosalee’s backstory and we get some familial stuff that goes back to some of the touchstones from the very beginning. It’s nice when they don’t abandon some of the groundwork that’s been made previously. They harken back to some of her issues in the past, which is nice.

Do you prefer working on the more serialized, longer-arc stories on the show or the more episodic, monster-of-the-week stories?

I think it has to be both. It’s a weird stew that has been seasoned sort of perfectly with these weird cultural references that have a cachet right now. I mean, who knew that Krampus was a thing? The actors are all very well cast. The location is perfect. The crew is full of serious badass artists who fight through the weather and pain of five-thirty on Friday and Saturday morning in two-degree weather. And storytelling-wise, it’s also this crazy stew that’s part procedural but it has a human drama thing going on and international intrigue and a spy story and a creature feature. It’s all of these things. It’s this weird blend, so it has to be all of these things. And I think that’s what makes the show so much fun.

Grimm’s Fall finale begins tonight at 9PM on NBC.