Christmas cheer comes to a halt when a menacing threat invades Portland; Monroe has a very special Christmas surprise in store for Rosalee.
After investigating a strange cluster of female deaths and disappearances, Nick sends Monroe undercover to get a whiff of a hypnotic suspect. In the meantime, a stranger shows up looking to avenge the death of his friend at the hands of a Grimm, but he'll have to get past Captain Renard.
On the heels of a shocking discovery, Nick is hell bent on getting revenge and taking the fight to the Royals with help from Trubel.
Monroe gets a call that will bring Nick closer to his ancestors. Things get complicated when Black Claw is also after the same artifacts.
The justification for Nick to become a Grimm again is made much clearer in the wake of the most recent attack against Monroe and Rosalee.