If the wesen of Portland need to learn one thing, it's that nobody - absolutely nobody - is to mess with Nick Burkhardt's family. Since the Grimm monsters seem to be a bit slow on the uptake, perhaps a new, more vicious version of the cop will get the message across.

The last two years have put Nick (David Giuntoli) on his back foot, causing him to throw up defenses left and right. Betrayals, murders, an attempts on his life colored seasons four and five, but it was Black Claw's decision to go after little baby Kelly that proved to be the final straw.

"I anticipate Nick is going to be very vicious in season 6," Giuntoli teased at Armageddon Expo in New Zealand. "He was very vicious in the finale of season 5. He turns."

The Portland detective received a compliment of superpowers when his Grimm legacy activated back in season 1, but it doesn't sound as if Nick will debut any new tricks as season 6 begins. Instead, Giuntoli's character will seek to up his game by flipping the switch on his dark side.

"Nick has gone through a lot of different phases of superpowers [but] those kind of tailed off as the episodes go on," Giuntoli explained. "I think they want to take Nick to - I don't know about superpowers - but I know they want to turn him into a fierce, aggressive, kind of unhinged character, so that will be really fun to play for me."

Viewers won't have to wait long to see Nick throw a few punches. Season 6 will pick up just seconds after the events of "Beginning of the End," setting the stage for a showdown with Renard (Sasha Roiz).

"He's face to face with Renard, so this could go two ways. Will there be a negotiation? Will Nick think this through? Or is he so furious at Renard for taking his child away that he'll just go crazy?" Giuntoli told TV Insider. "I would imagine the first scene in Season 6 will be a real melee with Nick and Renard."

Find out what's next for the Scooby Gang when Grimm returns to NBC this fall.

Tags: Grimm television nbc