Grimm: Season 4, Episode 21

4 - 21: Headache

In the course of investigating a grisly murder, Nick and Hank get closer to uncovering the identity of the serial killer while Wu's life is put in grave danger. Juliette, having turned down Monroe and Rosalee's offer, solidifies her new alliance as she works to get her revenge. Meanwhile, a dear friend makes a surprising return to Portland.