Originally Posted by Wikipedia

Set in present-day Portland, Oregon, the series puts a new twist on the stories of the Brothers Grimm in which a homicide detective learns that he is a descendent of a group of hunters known as "Grimms", who fight to keep humanity safe from the supernatural creatures of the world. Upon learning of his destiny and that he is the last of his kind, he has to protect every living soul from the sinister storybook characters that have infiltrated the real world.