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.

Deputy Police Chief Brenda Leigh Johnson transfers from Atlanta to LA to head up a special unit of the LAPD that handles sensitive, high-profile murder cases. Johnson's quirky personality and hard-nosed approach often rubs her colleagues the wrong way, but her reputation as one of the world's best interrogator eventually wins over even her toughest critics.