<Ul> <Li> David Giuntoli as Nicholas "Nick" Burkhardt, the eponymous Grimm . Nick is a Homicide detective whose Aunt Marie (Kate Burton) tells him that he is descended from a line of hunters, called Grimms, who fight supernatural forces . Even before his abilities manifest, Nick had an exceptional ability to make quick and accurate deductions about the motivations and pasts of individuals, which has now expressed itself as his ability to perceive aspects of the supernatural that nobody else can see . He temporarily loses his Grimm power after the event of Season 3 finale through a revenge scheme by Adalind, but regains them in the Season 4 episode "Highway of Tears". He later learns that Adalind is carrying his child, which is revealed to be a boy whom Adalind names "Kelly" after Nick's mother (Mary Elizabeth Mastrantonio). </Li> <Li> Russell Hornsby as Hank Griffin, Nick's Homicide partner, who is not aware that Nick is a Grimm until Episode 3 of Season 2 . He is somewhat sarcastic at times and has gone through at least four marriages by the time the series begins; nevertheless, he is Nick's best friend in the human world, becoming closer once again after Nick reveals the truth about his Grimm heritage and the Wesen out in the world . </Li> <Li> Bitsie Tulloch as Juliette Silverton (Seasons 1--4) and Eve (Seasons 5--6), Nick's girlfriend, a veterinarian . She is originally unaware of Nick's duties as a Grimm until he tells her in the finale of Season 1 . However, by Season 2, a magically induced amnesia removes Nick from her memory altogether, to the extent that she only forgets Nick while still remembering characters like Monroe when she only met him through Nick . Although Nick's Aunt Marie suggests that he leave Juliette for her safety, Nick decides to stay with her . He postpones his original plans to propose to her while he explores his new life as a Grimm . She eventually regains her memories and learns the truth of Nick's abilities, joining him in dealing with some Wesen - related problems, such as finding a cure for a disease that give human children the appearance of Wesen . In Season 4, a series of events and dangerous spells results in Juliette becoming an exceptionally powerful Hexenbiest, and her personality becomes drastically more antagonistic and less empathetic as a result, enjoying her power while disregarding her friends' concerns or hating Nick's allies for doing this to her . After her plans for revenge culminate in the death of Nick's mother, she is shot with a crossbow by Trubel in the Season 4 finale . In Season 5, Tulloch plays "Eve", a mysterious woman who has all of Juliette's memories and powers, but none of her emotional attachments . </Li> <Li> Silas Weir Mitchell as Monroe, a wolf - like creature called a Blutbad who aids Nick with his cases . He is also a good friend of Nick's, even though he has some issues with Grimms since a Grimm killed his grandfather (but he acknowledges that the ancestor deserved it for butchering a village). Monroe is knowledgeable about many of the wesen that Nick goes up against, serving as Nick's direct source of insight and information into the supernatural community whenever the second - hand knowledge that Nick acquires from his ancestors' books is inadequate, as well as assisting Nick when cases require Nick to rely on someone who knows about the threats he faces . He also helps Nick make contact with creatures that would avoid Nick due to his status as a Grimm . Eventually, Monroe falls in love with and marries Rosalee, despite facing some hostility from a Wesen cult focused on purity due to their mixed heritage . </Li> <Li> Sasha Roiz as Captain Sean Renard, a fluent francophone; Nick's adept and efficient superior . Renard is a magical creature called Zauberbiest and royal bastard . His mother Elizabeth (Louise Lombard) is a Hexenbiest, a witch; and his father is royalty, a fact of which Nick is not aware of until the middle of Season 2 . He is also the father of Hexenbiest Adalind Schade's daughter Diana . In Season 5 he is manipulated into running for mayor as part of a plan by pro-Wesen organization Black Claw, who seek to put Wesen in a position of power over humans rather than hiding among them . </Li> <Li> Reggie Lee as Sergeant Drew Wu, a police sergeant who works with Nick and Hank; he tends to do the "grunt work" for them, running down facts and information . In Episode 9 (at the beginning) of Season 4, Nick is forced to tell him everything about the Wesen world after he starts losing his mind due to all the "Wesen" involved murder cases . From then on he is a loyal member of Nick's team, providing an additional hand in the field . As of Season 5 when he is scratched by a Blutbad infected with Lycanthropia Wu is a Lycanthrope . At first unable to control his primal emotions, Wu eventually learns to control his transformations and is now able to woge into a Neanderthal like version of a Blutbad . </Li> <Li> Bree Turner as Rosalee Calvert (Recurring Season 1; Regular Seasons 2--6), a fox - like creature called Fuchsbau who takes over her brother's Wesen spice shop after he is murdered . Rosalee assists Nick and Monroe in their efforts by providing more information and remedies to supernatural problems, such as helping him extract a golden' tumor' from a bird - like Wesen or developing a cure for Nick's Wesen - induced blindness . She marries Monroe in the Season 3 finale and reveals she is pregnant in the Season 5 finale . </Li> <Li> Claire Coffee as Adalind Schade (Recurring Season 1; Regular Seasons 2--6), a witch - like wesen called a Hexenbiest who is working for Renard and who after ingesting Nick's blood becomes a normal human being . Seeking revenge, she poisons Juliette to forget all memories of Nick and starts colluding with Renard's half - brother Eric, eventually regaining her powers through agonizing rituals . She has a daughter with Sean, Diana Schade - Renard, who has unique powers . Later on, she gives birth by emergency c - section to her second child, a boy she names Kelly (after Kelly Burkhardt), whose father is revealed to be Nick as she slept with him during a complex ritual to take his powers that involved her disguising herself as Juliette . After Juliette is transformed into Eve, Adalind moves in with Nick to care for Kelly, the two even forming a relationship, but this is complicated by the Black Claw's attempts to use Diana to improve Renard's image in his mayoral campaign </Li> </Ul> <Li> David Giuntoli as Nicholas "Nick" Burkhardt, the eponymous Grimm . Nick is a Homicide detective whose Aunt Marie (Kate Burton) tells him that he is descended from a line of hunters, called Grimms, who fight supernatural forces . Even before his abilities manifest, Nick had an exceptional ability to make quick and accurate deductions about the motivations and pasts of individuals, which has now expressed itself as his ability to perceive aspects of the supernatural that nobody else can see . He temporarily loses his Grimm power after the event of Season 3 finale through a revenge scheme by Adalind, but regains them in the Season 4 episode "Highway of Tears". He later learns that Adalind is carrying his child, which is revealed to be a boy whom Adalind names "Kelly" after Nick's mother (Mary Elizabeth Mastrantonio). </Li> <Li> Russell Hornsby as Hank Griffin, Nick's Homicide partner, who is not aware that Nick is a Grimm until Episode 3 of Season 2 . He is somewhat sarcastic at times and has gone through at least four marriages by the time the series begins; nevertheless, he is Nick's best friend in the human world, becoming closer once again after Nick reveals the truth about his Grimm heritage and the Wesen out in the world . </Li> <Li> Bitsie Tulloch as Juliette Silverton (Seasons 1--4) and Eve (Seasons 5--6), Nick's girlfriend, a veterinarian . She is originally unaware of Nick's duties as a Grimm until he tells her in the finale of Season 1 . However, by Season 2, a magically induced amnesia removes Nick from her memory altogether, to the extent that she only forgets Nick while still remembering characters like Monroe when she only met him through Nick . Although Nick's Aunt Marie suggests that he leave Juliette for her safety, Nick decides to stay with her . He postpones his original plans to propose to her while he explores his new life as a Grimm . She eventually regains her memories and learns the truth of Nick's abilities, joining him in dealing with some Wesen - related problems, such as finding a cure for a disease that give human children the appearance of Wesen . In Season 4, a series of events and dangerous spells results in Juliette becoming an exceptionally powerful Hexenbiest, and her personality becomes drastically more antagonistic and less empathetic as a result, enjoying her power while disregarding her friends' concerns or hating Nick's allies for doing this to her . After her plans for revenge culminate in the death of Nick's mother, she is shot with a crossbow by Trubel in the Season 4 finale . In Season 5, Tulloch plays "Eve", a mysterious woman who has all of Juliette's memories and powers, but none of her emotional attachments . </Li>

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