|Owned by:|| Knighted ancestors of Grimms|
|Purpose:|| Map (exterior)|
|Location:||Hidden in the spice shop|
"The Good Shepherd" (picture only)
"The Law of Sacrifice"
Nick's Key is a small green item that folds much like a multi-tool or butterfly knife to hide its purpose. It is a key to fit a ward lock, which is unlocked using a set of instructions. ("Endangered") Marie Kessler gave the key to Nick Burkhardt after she had been attacked by Hulda. ("Pilot") Many people have attempted to obtain it for the Royal Families too, usually ending up being killed in confrontation with Nick.The page from the atlas included the point where fifty-two degrees north latitude intersects the shoreline of continental Europe. It seems to be somewhere in France.
Monroe instantly recognized the map as a river in the northwestern part of the Swabian Circle, meaning the treasure was hidden somewhere in the Black Forest. ("Endangered")
Renard proves to be very interested in obtaining it, and sent Adalind to extort it from Nick by placing Hank's life at stake. After poisoning him, Adalind demands Nick give her the key or Hank will die. However Nick manages to defeat her, by tricking her into drinking his blood, thus destroying her Hexenbiest side.The key is later revealed to have a map of some sort carved on the outsides of the folding arms. Nick accidentally discovers this when he spill ink on the key.
When Marnassier comes to Portland to receive the key, Kelly Burkhardt told Nick its origins. She reveals that the key is one of seven keys that belonged to seven knights who were ancestors to the Grimms. They worked for the seven families in the twelfth century. After sacking Constantinople in the Fourth Crusade, they took the treasure back, made a map on the seven keys, and each took a key. The keys, when put together, reveal the location of a treasure. The treasure is supposed to be an artifact so powerful that, if held by the seven royal families, it would allow them to rule the world.
The Nuckelavee searches Nick and Juliette's home looking for the key, equipped with a sketch depicting the key. He then follows Nick to the trailer where he confronts Nick and is killed by a hammer to the head. When Nick searches his body he finds the sketch.
Adalind arrives in Portland and tells Sean Renard that he has 48 hours to procure the key and and give it to her, otherwise she'll tell Nick that she was working for him when she tried to kill Marie Kessler.
When being interrogated by Nick, Adalind strongly hints that it would be better for everyone if he gave up the key. Later, Adalind privately tells Nick that if he gives her the key, she'll tell him the identity of the Royal in Portland for whom she was working when she tried to kill his Aunt.
Renard searches the trailer looking for the key, but does not find it. He then remembers Nick putting something in his desk, so searches Nick's desk. He takes the key from Nick's desk at the precinct and later, after confronting Nick regarding Juliette and revealing himself to be a Zauberbiest and the Portland Royal, returns it to him.
Nick shows the key to Hank and explains its Fourth Crusade origins and the supposed map it helps form to find a powerful and dangerous artifact. He also reveals he's wearing it around his neck, so now anyone who wants it will have to kill him to get it.
Nick decides to show the key to Monroe, prompting Monroe to recognize it as a map of a German landscape and compares it to an old style map of Schwaben he inherited from his great-great-great-grandfather. After casually referring to the area as including the Black Forest, Monroe shows Nick how the notation on the key resembles that on the map. Nick explains the involvement of Grimms in the Fourth Crusade. After telling Monroe that he does not know where the other six keys are, Nick decides to talk with Captain Renard.
Although their conversation is testy, Renard verifies that the seven crusaders, who were all Grimms, kept something from their patrons. The Seven Houses found out about the deception and set forth to recover the keys and the hidden treasure. They severely tortured one Grimm until he betrayed his brothers. Over the intervening centuries, the Royals have acquired four keys, however it took considerable bloodshed, even by their standards; the locations of two keys are unknown to Renard; Nick's key is the last. There is no identified order for the keys.
The nature of the treasure is uncertain. Renard mentions four possibilities: the secret of alchemy, everlasting life, the prophet Muhammad's Sword, the nails that held Jesus Christ to the Cross and possibly pieces of the Cross itself.
Before Juliette, Hank, Monroe, Nick an Rosalee head to the container yard to deal with the Cracher-Mortel zombies, Nick gives Rosalee the key to keep safe, which she hides a compartment under some loose floorboards in the spice shop.
- The appearance of the key changed during the first season. When the key is first seen in the pilot episode, the etched image on both sides is that of, what looks to be, a creature. Later during the season, the etchings changed into a map.
- Although not explicitly stated, it looks like the key is made from bronze, which has oxidized green due to the artifact's age.