After a dark and twisted season of "Grimm," Season 4 of the popular sci-fi series will come to an end on Friday when Nick and Juliette finally go head-to-head in an epic showdown.

In addition to battling the Royals, Nick will go on the hunt to track down Juliette, who he believes played a role in killing his mother and kidnapping baby Diana.

A preview clip from Friday night's season finale, "Cry Havoc," teases the moment Nick comes to the realization that Juliette set up his mother. In another clip, Monroe and Rosalee's quiet evening at home is interrupted by Trubel and Bud, who frantically knock on their front door to share some very bad news. It turns out that something terrible has happened and that they all are in grave danger.

Another sneak peek shows that Wu will insist on joining Nick, Hank, Monroe, and Trubel in their hunt to take down the Royals. After discovering that Nick's mother, Kelly, was brutally murdered, Wu will feel compelled to help defeat the Royals. In the video, he follows the team into the woods and insists on joining their hunt for the Royals.

"Should I still bring a shotgun ... just in case?" Wu asked the team.

"You never know," Hank responds.

According to Dread Central, the synopsis for Friday's finale is below:

"On the heels of a shocking discovery, Nick (David Giuntoli) is hell bent on getting revenge and taking the fight to the Royals with help from Trubel (guest star Jacqueline Toboni). Meanwhile, Juliette's (Bitsie Tulloch) alliance continues to lead her down a dark path."

"Grimm" Season 4, Episode 22, "Cry Havoc" airs on Friday, May 15, at 8 p.m. EST on NBC.

Watch preview videos below.