Nick and his allies take the offensive against Black Claw after his friends rescue the Grimm from police custody. Meanwhile, Rosalee gives Monroe some news, and Eve is mortally wounded.
Black Claw frames Hank for murder as a means to interrogate him for what he knows about Nick. Meanwhile, after Black Claw wipes out HW, Nick attacks Renard and is thrown in jail.
Renard and Adalind come together over their children and Black Claw's intervention. Meanwhile, Nick learns of Renard's involvement and confronts the captain. Wu gains control of his transformation, and Hank discovers that Zuri is playing him.
While Wu's nightmares lead him into a murder investigation, Hank and Zuri closer. However, Hank is unaware of Zuri's true intentions. Meanwhile, Renard and Black Claw representative Conrad Bonaparte both advise Adalind to join Black Claw or face the consequences.
Nick and Hank investigate the death of a drunk driver where every bone in his body was removed. Meanwhile, Wu begins to realize something is wrong with him, and Eve warns Rosalee about Adalind reverting to her Hexenbiest self.
A teenager is decapitated, and Nick and Hank discover that the murder is Wesen-related. Meanwhile, Adalind goes back to work at her old firm, after receiving a warning from Eve.
Nick and Hank investigate a death at a tent revival and discover that the preacher who claims to be possessed by Satan is actually a Wesen. Meanwhile, Eve infiltrates Black Claw posing as Renard, and Monroe convinces a friend to help them translate the cloth.
A Wesen who can extract the youth from his victims enter into an unholy alliance with a "Fountain of Youth" beauty clinic. Meanwhile, Eve continues her investigation into Andrew's assassination.
While Eve continues her investigation into the Dixon assassination, Nick and Hank track down a killer who strikes on the nights of the full moon. Meanwhile, Renard tells Adalind that their daughter is still alive.
Nick and Hank tie two murders to an ancient Wesen ritual designed to imbue Luchador masks with the power of its owner... after the owner's face is flayed off to make the mask.
While Nick and Monroe search for the Crusaders' treasure, Rosalee and Adalind deal with Rosalee's former boyfriend. Meanwhile, Renard discovers who is responsible for Dixon's assassination and receives a shocking offer.
With Nick and Monroe off to the Black Forest, Black Claw launches a major attack on Portland.
Black Claw tries to trace down a cache of Grimm books that have fallen into the hands of Monroe's uncle. It's a race against time as Nick and his friends try to get the books before the Wesen killers do.
A killer murders two victims as part of an ancient Wesen ritual, and Nick discovers that it's tied to Black Claw. Meanwhile, HW demands to meet with Nick and his team to discover where their loyalties lies.
While Meisner shows Nick the HW operation in Portland--and Eve--Nick and Hank investigate a grisly murder seemingly committed by a legendary lake monster. Meanwhile, Rosalee receives another letter from her old drug buddy in Seattle.
The Black Claw organization goes public, wiping out the Council and vowing vengeance for the followers that the new Juliet killed. Meanwhile, Nick confronts Trubel and then Meisner about what happened to Juliet.
The Uprising launch an attack on the Wesen shop owners of Portland, and Nick and Hank soon get a lead on tracking them down. Meanwhile, Trubel brings Nick up to speed on what she's been doing, and Nick sees a figure from his past.
Nick and Hank investigate the deaths of two Wesen who went Reinigen hunting at a local dump and ran into something more than they could handle. Meanwhile, Nick takes Trubel to the hospital, and Meisner finds Nick's fortress... and Adalind.
An aging mobster sends three Wesen men out on a quest to win his daughter's hand... by killing the man who killed his son. Meanwhile, Nick and Adalind continue adjusting to life together at the fortress, Rosalee receives a letter from someone she knew in her addict days, and Renard is asked to support a mayoral candidate.moreless
The body of a woman missing two years turns up, and Nick and Hank soon discover that she's tied to a group of homeless Wesen children... who have abducted Rosalee to serve as their next mother. Meanwhile, Meisner pays Renard a visit, and Nick finds a new home after selling the old one.moreless
When a Wesen embezzler kills his boss, Hank has to work with a new partner while Nick is on leave. Meanwhile, Adalind and Kelly move in to Nick's house.
Mysterious attackers knock out Nick and take Trubel, and he believes that Agent Chavez is responsible. Nick's friends begin to question his sanity in the wake of Kelly and Juliette's deaths, while Adalind goes into labor.