- David Giuntoli (Nick Burkhardt)
- Silas Weir Mitchell (Monroe)
- Russell Hornsby (Hank Griffin)
- Sasha Roiz (Sean Renard)
- Reggie Lee (Drew Wu)
- Bree Turner (Rosalee Calvert)
- Claire Coffee (Adalind Schade)
- Elizabeth Tulloch (Eve)
Grimm — S4E21
Episode: Headache
Air Date: 2015-05-08
Runtime: 43 min
Overview
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.