An Oregon police detective learns that he has inherited the ability to see dangerous creatures who pose as real people, sending his life into turmoil as he looks for an abducted child while learning what it means to be one of the last of the Grimms.
A breaking-and-entering case turns into a missing person investigation, leading to a family of bear-like creatures who are planning a ritual hunt. Nick asks his new Blutbad friend to protect his dying aunt.
After a victim is murdered by bee stings during a flash-mob, Nick and Hank must protect a monster in hiding in order to reach the hive of killers ... "Clarions" who harbor a dire warning for the Grimm.
After the death of a young girl Nick and Hank investigate a suspected serial rapist, who is actually a creature who seduces women with powerful pheromones. Meanwhile, a stranger comes to town looking to take revenge on a Grimm.
Nick investigates an arson case after a man is nearly killed when his house explodes, leading him to a supernatural family feud. Monroe is reunited with an old girlfriend who tries to lure him back to the wild side.
After a murder in the woods Monroe and Nick go in search of a wild Blutbad who has been living alone since she was a young girl, while Hank reopens her missing persons case.
A super-strong killer who can't be stopped by bullets targets the people who put him behind bars. After Nick is put out of action he must rely on Monroe to stop the creature before Hank becomes his next target.
Nick tracks a string of homicides to a mouse-like man who is looking to escape his childhood and find a new life with the girl next door. Monroe is attacked by other creatures, and Juliette is convinced that her house is being watched.
The detectives track a spider-like femme fatale who leaves the bodies of her victims dessicated. Meanwhile, Nick realizes that he has gained too much notoriety in the creature community.
The murder of a retired couple by a carnivorous creature leads Nick to a gladiator-style fight club run by Wesen, who kidnap promising fighters in the woods.
A jewelry store robbery leads Nick to a group of Wessen looking for a trio of rare coins that give their possessor remarkable strength and charisma, which begin to affect his coworkers.
The murder of the local exotic spice shop owner leads Nick to a pair of drug-seeking creatures. Meanwhile the man's grieving sister arrives in town, and Adalind schemes to put Hank under her control.
On a romantic getaway with Juliette, Nick encounters a catlike man who appears to be holding his bird wife captive in their remote home. Hank's interest in Adalind begins to grow obsessive.
After Captain Renard is confronted by members of "the family," his associates become the victims in Nick and Hank's latest case. Nick is disturbed to learn about his partner's new love interest, and must intervene when Sergeant Wu's condition worsens.
After a construction worker witnesses a murder, Nick asks his ice beaver family to convince him to come forward and testify. Meanwhile, Juliette invites Monroe over for an inevitably awkward dinner, and a pair of Reapers arrive in Portland to kill the Grimm.
A wealthy woman is murdered in her home after denying money to her stepdaughter's husband, sending Nick and Hank to investigate the family's financial problems. Juliette looks into the deaths of Nick's parents in 1994.
A gruesome double homicide in the woods suggests Bigfoot as the culprit. But after Monroe learns that his friend Larry was responsible, he and Nick must throw the police off the scent while investigating a doctor pushing a supposed "cure" for Wesen urges.
One of the men responsible for the death of Nick's parents arrives in Portland in search of the powerful gold coins, targeting Nick and his co-workers. Adalind draws Juliette into her plans, prompting Nick to reveal his secret.