This has been the darkest season of "Grimm" so far, with Juliette's downward spiral, baby Diana re-emerging in Portland and Adalind carrying Nick's child. How will this season end?

It appears that the end will be full of revenge. TVLine spoke to co-creators James Kouf and David Greenwalt who teased that Nick would become hell-bent on taking revenge on the Royals after making a shocking discovery. No doubt, this so-called discovery will enrage the Hexenbiest. TVGuide notes that Nick will not be alone in taking revenge, as his mother and Trubel will also back him up. The Royals will obviously enter Portland to get their hands on baby Diana. Greenwalt confirmed, "Everybody wants to get their hands on her, and the Royals have brought out all the big guns for this."

The show's creators have teased at least two deaths, with the good guys getting in more trouble than the bad ones. Monroe will be shot, as the creators jokingly admitted that shooting the captain takes place in every season. However, this time around, Monroe will be shot by someone he considers to be a friend. Apart from these teasers, Kouf has admitted that towards the end of the episode, Nick would learn that he is the father of the child being carried by Adalind.

Viewers looking for a now sinister Juliette to transform back into her sweet veterinarian self will be sorely disappointed, as she continues down a dark path. Her new alliance strengthens, making fans question if she has gone over to the dark side for good. Now that baby Diana is with Juliette, it remains to be seen what the Hexenbiest will do with her. Silverton is obsessed with settling scores with Adalind after she learns that she is carrying Nick's child. What will she do to Adalind's baby, Diana?

"Grimm" airs its finale on Friday, May 15 at 8 p.m. EST on NBC.