Perhaps it's fitting that Silas Weir Mitchell, who plays the werewolf-like "Wieder Blutbad" Monroe on NBC's "Grimm," has great concern for real-world creatures. "To me, the most tragic, awful thing that's happening in the world right now is what's going on in Africa with people killing rhinos and elephants for their horns and ivory. That makes me murderously enraged," says Mitchell. "There's a certain country that drives the demand for this stuff and that's gotta stop." A lifelong animal lover who grew up with pet dogs, cats,  birds and snakes, he has a dog now, and his wife works for Wildworks animal sanctuary. "They take wild animals that are unable to integrate into the wild because they've either been pets or the people couldn't handle them or they were injured and brought there," he says.

"Grimm" was honored last year with the "Green Award" for its eco-friendly practices at the Travel Portland Tourism and Hospitality Industry Awards, and Mitchell thinks that's "Fantastic. The clock is ticking, man, so whatever you can do, you should do," he says. "Like don't drink half a bottle of water and leave it there."

"Grimm" returns with new episodes March 8, and Mitchell has a theory about its popularity. "It's a hybrid, familiar enough in the procedural sense, but also 'other,' so you recognize it and are intrigued by it at the same time." Also, the stories are timeless — and a bit twisted. "Grimm fairytales are very dark but they're also about identity, danger, betrayal." Playing Monroe, "I feel like I'm having more fun than a guy should have," he says, citing the writing, cast and crew, and themes that are "really pertinent and they're handled in a very delightful way. There's dark, there's light, there's a gallows humor. And we're dealing with crime and real stuff. There's nothing I don't like about this situation."

For Mitchell, who knew he wanted to act way back in the third grade, it’s "the most consistent work I've had, because I came in on the ground floor, which I've never done. I sort of parachute into places and stay for a few episodes. So this is not only the longest running but it's coming in from the get-go," he compares. He finds Monroe's childlike nature, blasé attitude, wry humor, and his role as a bridge between the Wesen (creatures) and Grimms (hunters, personified by his friend Nick (David Giuntoli) "delightful to play," especially now that he has a love interest in Rosalee (Bree Turner). The pair are on "a slow progress to intimacy. Our storyline is carrying on but we also operate within these other storylines. For Monroe," he adds, "It's more about helping where he can and trying not to break things."

Occasionally, Monroe is seen as his true Blutbad self, thanks to CGI. "They place little dots on your face to do the morph and un-morph sequences," put together by "a whole team of brilliant people who design the look of the creatures and people who execute those designs," he says gratefully. "If I had to do full makeup it would be like 10 hours."

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'Grimm' star Silas Weir Mitchell speaks up for wildlife
Animal poaching makes Silas Weir Mitchell ('Grimm') 'murderously enraged'.