Russell Hornsby Russell Hornsby

Fighting crime in the world of Grimm is rather hard on an unsuspecting police officer who has no clue that monsters are real.

On Monday's episode (10/9c, NBC), Portland Det. Hank Griffin (Russell Hornsby) is still struggling to comprehend what he saw when a Wesen transformed from a creature back to human right before his eyes. "Hank has lost his mind. He's questioning his sanity after having seen creatures morph," Horsnby told reporters. "It's taken him off of his axis. He's seeking professional help and going to therapy, seeing if he can get back his center."

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That precarious mental state will be tested on Monday's episode, "Bad Moon Rising," when Hank encounters a childhood friend who needs help finding his missing daughter. What Hank doesn't know is that old pal Jarold (guest star Mark Pellegrino) is actually a coyotl, a coyote-like Wesen. Whether or not the cop can handle witnessing another surprise transformation, especially when it's someone he knows, remains to be seen.

Unfortunately, Hank's personal crisis could also affect his professional life. "He's questioning everything now: What's happening? Who's who?" Hornsby said. "Should he remain a police officer on the force or not? That's his new hero's journey."

It's bad enough that Hank doesn't trust his own instincts anymore, but he could face worse trust issues if he ever finds out that his partner Nick (David Giuntoli) is mixed up in this fantastical world and neglected to clue him in. "I believe what you tell me," Hank told Nick in the last episode. "But whatever you do, don't hang me out to dry."

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As a Grimm, Nick is blessed/cursed with the ability to see past the human face and recognize the Wesen identity below the surface. Withholding this information to protect the people in his life seems to have the opposite effect. Not only did a Hexenbiest named Adalind cause Nick's girlfriend Juliette (Bitsie Tulloch) to fall into a coma and lose her memory, but that same creature once gave Hank a love potion in chocolate-chip cookie form, which sent him into a comatose state.

If Hank ever discovers the true nature of whom he once climbed into bed with, it's safe to say he won't be trying to date another Wesen anytime soon. "I'm just hoping for a love interest at this point," Hornsby joked.

Check out this preview of Monday's Grimm, airing 10/9c on NBC. The series moves to Fridays at 9/8c beginning Sept. 21.