"Grimm" has been pretty good at handling how they will end every season - endings that provide a resolve to the season's story arc, yet leaves a scene that opens the door to a new conflict for the upcoming season. The series has been full of mysteries, and the heritage of the show main protagonist, Nick Burkhardt portrayed by actor David Giuntoli offers a lot of angles to delve into.
The past season saw Nick and his friends getting in some tight spots, and along the hardships comes injuries - injuries which could have been fatal if not for a certain "magical stick" with mysterious healing properties. This season finally answered the question of where the keys of the Grimms leads to, and information that they gathered over multiple episodes finally explained the origin of the Grimms and the treasure that they have guarded with their lives.
The stick that Nick has found inside the chest that the Knights Templar or the Grimms have protected is a lingering mystery even with the show's interesting season finale. One of the cliffhangers from the last season was Eve, who formerly Nick's fiancee, Juliet had been seriously injured but was healed by the stick. All seems good, but it was revealed that amidst Eve being healed, her personality has also been changed, but was left to be vague.
According to Vine Report, based from a recent discussion with Enstarz during the 2016 San Diego Comic Con, David Greenwalt, series creator of Grimm teased fans that the mystery of the stick will be look more into in the upcoming season. This includes its origins and further show its abilities. David also mentioned that the stick will have negative properties, too.
Also David Giuntoli, in a talk with TV Insider, gave hints that what ever Nick knows will either be soon revealed to the rest of his friends or not, and all depends on his circumstances.
Video courtesy of PopWrapped Entertainment Group
