Grimm Season 4 Episode 21 — Headache

While 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. Having turned down Monroe and Rosalee's offer, Juliette solidifies a new alliance as she works to get her revenge. Elsewhere, Trubel makes a surprising return to Portland.

Grimm Season 4 Episode 21 (“Headache”) is episode 21 of 22 in Season 4 and first aired on May 8, 2015. It runs about 43 minutes. Directed by Jim Kouf. Written by Jim Kouf and David Greenwalt. Guest stars include Danny Bruno, Garcelle Beauvais and Kate Holdaway. Grimm is a Drama, Mystery and Sci-Fi & Fantasy series from NBC.