Nick Burkhardt (David Giuntoli) may have finally put his beef with Renard (Sasha Roiz) aside — for the time being — on Grimm, but there's a much larger danger than the police captain and Black Claw awaiting the Scooby Gang.

So far in the final season of Grimm, "The Stick" has only saved Eve's (Bitsie Tulloch) and Nick's life, but as we got a glimpse of in this week's episode, very soon the mystical artifact Nick and Monroe (Silas Weir Mitchell) dug up in the Black Forest is going to be less of an asset and more of a worst nightmare.

"The stick is not just going to be a little stick. It's the worst stick in the world," Giuntoli tells TVGuide.com "One of the lessons we've learned is that if something has been buried for hundreds and hundreds of years, just don't go looking for it. If it was intentionally buried, just leave it alone. The Grimm ancestors put it there for a reason and now Nick is becoming sort of addicted to the stick."

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Nick in particular is the most at risk when it comes to the stick's immense power. It's already caused him to lose his temper, but it's only going to get worse from here, according to the actor. "It affects Nick in a huge way. The implications of them digging that stick up changes everything. It is an end game kind of plot point," he says. "You're playing with universal powers and one thing you learn is that you can't just take the good. There's plenty of side effects and events that we don't understand by us using this stick."

The effects go far beyond Nick's addiction to the stick's power. It is also bringing Juliette out of her steely Eve shell — which makes things extremely complicated for Nick and Adalind (Claire Coffee). The latter two are just starting to get their lives back together and finally can return home to their loft to raise their son, Kelly. Having Nick's ex revert back to her completely normal self is going to make for a very awkward living situation.

"It makes things very difficult. I don't know if he can act on those impulses. That's the last thing he wants in his life. When you see Juliette, and she apologizes for all that happened when she was Eve, it's hard. Clearly, Nick is torn," Giuntoli teases. "He and Adalind are solid right now. It's this unrequited thing with Juliette. She kind of bounced on Nick, but she was under this spell of something else. It's a very difficult emotional thing for Nick to go through."

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However, it may not be as simple as Nick having to choose between Juliette and Adalind, because fate has other plans for the Grimm that he may finally have to accept before the season is over.

"From the very beginning he's been warned from people — from his aunt to his mother — you can't have these relationships. They have to go. You are putting everyone you love in danger. Throughout the seasons, it's really become true." Giontoli explains.

If Nick truly embraces his role as the Grimm, it may be a very lonely road ahead.

"I think that he wants to be Nick the cop, but the fate that is showing up is that he has to be the Grimm. He can no longer be Nick the boyfriend, the cop, the father, the pal. He's the Grimm," the actor continues. "He's got a tremendous amount of responsibility on his shoulders and until he full embraces that, all of his loved ones are going to be in peril, and oh my God are they ever in this season."

Grimm continues Friday nights at 8/7c on NBC.