"Grimm" will be hitting its 100th episode come season 5 titled "Into The Schwarzwald. As a treat to the fans, showrunner Jim Kouf confirmed that the mystery surrounding the Seven Keys will finally be revealed.
Speaking to Movie Pilot, the show creator admitted that they were surprised that the show went on for so long. During the first season, Kouf said that they will only think about answering questions about the keys once they get to their 100th episode. He added that they did not really had a concrete idea of what those keys are and had to decide when they reached the 90th episode.
"When we got to 90 and 91 and 92, we go, 'Uh-oh, we'd better figure out what those keys are.' So, I mean, we always had an idea, but now we had to actually do it," he said.
The outlet pointed out that not much is known about the seven keys, except that it opens the door to buried treasure.
The treasure/artifact is reportedly so powerful that it would allow the Royals to rule the world. It was said that the treasure could be: Muhammad's sword, the secret of alchemy, the key to immortality or the nails used in Jesus' crucifixion/ pieces of the cross itself.
It was also said that the last missing key will finally show up in the 98th and/or 99th episode, titled "Map of the Seven Knights" and "Key Move," respectively. The Royal families currently have four of the seven keys in their possession.