Expect an emotional finale as popular Portland-filmed NBC series comes to an end

COURTESY: NBC UNIVERSAL - The self-described 'Scooby squad' of 'Grimm': (from left) Reggie Lee, Bitsie Tulloch, David Giuntoli, Russell Hornsby, Claire Coffee, Silas Weir-Mitchell, Bree Turner and Sasha Roiz. They'll be filming their season 6 finale in Portland this month, full of sentiment and emotion.What can fans expect from the final season of “Grimm,” the supernatural police show filmed in Portland?

A lot of revelation and answers, as the popular NBC show comes to an end after six seasons. The 13-episode season starts Jan. 6, and shortly thereafter in real time, the cast and crew gather again in Portland to film the season finale — episode No. 123.

“We can’t have a big cliffhanger,” says David Greenwalt, co-creator with Jim Kouf. “We’re wrapping up our precious baby and everybody we love and adore ... We’ll go full circle; you’ll see (links to) the pilot.”

Adds Kouf: “We did right by the characters. Hopefully it’ll be right for the audience.”

“Grimm” began in 2011 as part of a lineup that NBC hoped would elevate it out of the ratings basement. It has helped, and “Grimm” has withstood the test of time — it’s the only show remaining from the debuts of 2011.

For those who haven’t watched “Grimm,” it’s a police procedural based on the Grimm fairy tales, in which a descendant of the powerful Grimm family (Det. Nick Burkhardt, played by David Giuntoli) leads a “Scooby squad” of crime fighters against a secret society known as Wesen. The “Scooby squad,” as the actors called themselves, are made up of: Burkhardt’s partner Hank Griffin (Russell Hornsby), girlfriend-turned-nemesis Juliette Silverton/Eve (Bitsie Tulloch), Wesen friend Monroe (Silas Weir-Mitchell), Wesen/Monroe’s wife Rosalee Calvert (Bree Turner), conflicted Capt. Sean Renard (Sasha Roiz), nemesis-turned-girlfriend Adalind Schade (Claire Coffee) and funny Sgt. Wu (Reggie Lee). A second Grimm entered the picture — Trubel, played by Jacqueline Toboni — as has the very powerful daughter of Renard and Schade — Diana, played by local pre-teen Hannah R. Loyd.

COURTESY: NBC UNIVERSAL - Local actor Hannah R. Loyd's character Diana plays a big part of season 6.For those who have watched “Grimm,” here’s what to expect:

The “Black Claw” consortium of Wesen will be defeated, but a much more formidable force being/power challenges the world. “Cosmically bad,” Kouf says, with some quantum physics, prophecy and religion mixed in. Everybody unites to fight.

The story behind the keys and magical stick will be told.

Renard loses his job as mayor, returning to captain.

Burkhardt and Renard have a showdown.

Eve starts to return to her life as Juliette.

Diana plays a major role.

And, the finale will be epic and emotional. Get your tissues ready, Toboni says.

“We were, legitimately, shaking reading the finale. People were crying,” Turner says. “They did a beautiful job. Fans will really be satisfied and they’ll be (expletive) themselves.”

Says Tulloch: “There’s some brutal stuff, and the villain is extreme.”

“A lot of things happen to all of us,” Lee says. “They’re going out with a bang ... They are fantastic episodes with some closure, but it leaves it open. Fans will be happy.”

Adds Giuntoli: “I’ll say this: the final act is perfect.”

COURTESY: NBC UNIVERSAL - David Greenwalt, left, and Jim Kouf were the brains behind 'Grimm.'• Greenwalt and Kouf have quite a résumé together — seven seasons of “Buffy the Vampire Slayer,” five of “Angel” and now six with “Grimm.”

Nobody thought “Grimm” would take off.

“If we all knew that,” Kouf says, “we’d all have bought houses here and put our money in the Pearl,” a reference to Roiz, Giuntoli/Tulloch, Coffee and others buying homes and condos here.

The first season’s final, 13th episode had a reference to Hitler being a Wesen from the Blutbad clan — just in case the show wasn’t picked up, it was going to be a good ending.

“Fortunately we were able to go and go and go,” Greenwalt says.

“I didn’t even unpack my bags. ‘Ah, we’ll be canceled any day,’” Roiz says, of the first season. “We were like the red-headed stepchild (to NBC). Then we were moved to four different time slots, and the fans came along.”

• Greenwalt and Kouf moved on from the premise behind “Grimm” — modern-day “Grimm” fairy tales — to involve more mythology from Japan, Africa, Europe, Native America, religion.

“It’s less important what the fairy tale is,” Greenwalt says. “It’s more about what’s great storytelling that involves myth and legend.”

The show stuck to two other premises: Examining the monster within, “giving a face to what we call monstrous behavior,” Kouf says; and, the monsters within having their own stories and perceptions, such as “they’re scared of the Grimms,” Greenwalt says.

• The actors have grown close through their association with the show.

It’ll be tough to move on. Some of them have other jobs, including Hornsby, who’ll work in the Netflix series “Seven Seconds.”

Says Coffee: “We’re all feeling sentimental about it, but so grateful.”

Tulloch says she heard “horror stories” about casts not getting along, but the “Grimm” folks really liked each other.

“Everybody put team ahead of everybody else,” Hornsby says.

“There’s not been one negative experience on this show,” Turner says. “That’s really rare. We still love each other.”

Lee says while the actors will see each other in Los Angeles and elsewhere, it won’t be the same.

Says Roiz: “Nobody really wants to say goodbye. Our lives would feel incomplete without all of us together the last six years.”

Turner says the actors were “family” and Coffee was her good friend — both have children.

“We’ve leaned on each other so much,” Turner says. “We share nannies, cars, taking care of each other. It’s a unique thing to be working on a TV show with young babies at home.”

Overall, “there honestly was never a sour kind of feeling. We kept it pretty great,” Giuntoli says.

• Giuntoli and Tulloch started dating during season 3. They are engaged and could live, at least part-time, in Portland.

“It was really funny falling in love with your co-worker; we were trying to hide it from everyone,” Tulloch says. “We didn’t know if it would be serious. At some point somebody said, ‘No, we totally know you are totally in love with each other.’ We thought we were going to be covert about it.”

COURTESY: NBC UNIVERSAL - Being the lead actor of 'Grimm' hasn't affected David Giuntoli's personality, friends say. Says fiancee/co-star Bitsie Tulloch: 'He had to carry the show. He just really settled into that.'• Tulloch, who has made several movies during her time on “Grimm,” has watched the growth of the lead actor Giuntoli, who previously starred on MTV’s “Road Rules” among other things.

“It was a lot of pressure on his shoulders,” she says. “He had to carry the show. He just really settled into that. At our NBC dinner I stood up and gave a speech, and said David could have become a jerk over the course of six years. That happens to a lot of actors. He is the kindest guy; it’s one of the reasons I’m marrying him. He’s very humble and he just doesn’t have an ego.”

Says Giuntoli: “I never became a real, true (jerk). People tell you that you have to become one off screen ... If you’re a jerk all the time, no one cares anymore, you’re just a horrible thing to be around.”

Adds Giuntoli, who directed an episode in the final season: “It’ll be fun to see what happens next. I’m looking forward to a break. I’m not going to clamor for the next thing at all.”

• Toboni, 24, came straight from the University of Michigan to “Grimm” to play the second Grimm fighting the Wesen.

“I didn’t even know how to hit a mark when I showed up,” she says. “They took care of me and taught me everything I know. I’m so thankful.”

Then again, none of the actors were very well known going into their roles on “Grimm.” Hornsby had been on “Lincoln Heights” and others had sporadic success.

“We’ve all grown in a manner of speaking on this show,” Hornsby says. “We were adults, but we all became grownups on this project.”

Roiz says the show put the actors on the map.

“It’s not necessarily the only thing I want to be remembered for,” he says, “but it’s something I’m proud of.”

“None of us is a big movie star or TV star,” Weir-Mitchell adds. “And, here we are still alive. You just never know. ... God bless our fans. They stayed with us.”

COURTESY: NBC UNIVERSAL - Wesen creatures and special effects help make 'Grimm' fun to watch.• Sgt. Wu (Lee) provides much of the comic relief, but the show by its nature — fictional monsters and drama — just makes it a fun watch.

“What I love about ‘Grimm’ is it doesn’t take itself too seriously,” Turner says. “I think maybe the fans see an unexpected new development and it’s, ‘Ok, yeah, this works, too.’ Anything goes. Being on a genre show like this, especially one that blends drama and humor and supernatural, magical elements and action, we never get too heavy in one space.”