Board Thread:Episode Discussion/@comment-3125844-20150731045049/@comment-1509826-20150802111700

Bheadr27 wrote: They saved Diana from getting to close to the royals, so using her when she is still so young for espionage on the keys is... very unlikely. Maybe when she's grown up (perhaps at the end of the season going by her grow-rate XDD )

Renard told Nick, that the royals have 4 keys, but it's not neccessarily only one family, that got all of them. We were told about 7 houses, so... the keys could be anywhere in europe.

One key 'went into hiding', but since the Hundjäger were after the Porters, I guess that wasn't the lost one.

So, Nick has two, one is missing, four are with the royals.

Given that, I would say Nick/Trubel are searching for the lost one.

Agreed, I imagine it will turn out to be a with another very old and powerful Grimm family (its implied Nick's was one of the most, as they had the oldest Grimm Dairy in existence. Josh's was confirmed to go back to the middle ages.) So its bound to be with on of them. Come to think of it, Rubel is derived from a middle German name, dating back to the 7th century.

Interesting.