After Portland homicide detective Nick Burkhardt discovers he's descended from an elite line of criminal profilers known as "Grimms," he increasingly finds his responsibilities as a detective at odds with his new responsibilities as a Grimm.

Hard-edged cop John Kimble gets more than he bargained for when he goes undercover as a kindergarten teacher to get the goods on a brutal drug lord while at the same time protecting the man's young son. Pitted against a class of boisterous moppets whose antics try his patience and test his mettle, Kimble may have met his match … in more ways than one.