Goakes

I've had a theory on Hank for the last couple of seasons and his mysterious history kind of feeds in. Look at his name--Hank Griffin. A Griffin is a mythological beast also used by the brothers Grimm in their story "The Griffin". Within that story, one of the main characters name is Hans--which translates to Hank (really). See where I'm going here. I think Hank is Wesen and for some reason doesn't know it; or he is such a bad-ass Griffin that he is able to hide it from everyone. If that's not the eventual storyline, it's a rediculous coincidence.