The series' narrative follows Portland homicide detective Nicholas Burkhardt (played by David Giuntoli), who discovers he is a Grimm, the latest in a line of guardians who is sworn to keep the balance between humanity and mythological creatures, known as Wesen.

The series features a supporting cast with Russell Hornsby, Bitsie Tulloch, Silas Weir Mitchell, Sasha Roiz, Reggie Lee, Bree Turner, and Claire Coffee.

Throughout the series, he must battle against an assortment of dangerous creatures with help from his Wesen friend, Monroe, and his partner, Detective Hank Griffin.

Many of the episodes are loosely based on stories published by the Brothers Grimm, albeit with considerable artistic license taken.

[9] In January 2011, NBC announced that they had given a pilot order to a series titled Grimm, pitched by David Greenwalt and Jim Kouf.

[10][11] In May 2011, NBC picked up the pilot to series,[12] eschewing another supernatural police procedural, Ronald D. Moore's 17th Precinct.

[19] NBC aired a special Thursday screening on December 8, 2011, at 10 pm to analyse whether the network's overall ratings could improve.

[19][20] The creation of the titular Grimm books that are used on the show and featured very prominently were drawn by Oregon artist Carly Sertic[21][22][23] On March 16, 2012, NBC announced that the series had been renewed for a second season;[24] according to writers/producers David Greenwalt and Jim Kouf, they would continue to film the show in Portland, saying, "Rain or shine, Portland has been the ideal setting for fairy tales with its enchanting layout.

[35] David Giuntoli was the first to be cast in the series, in the titular role of Nick Burkhardt, in February 2011[36] He was followed by Silas Weir Mitchell as Monroe, the now-reformed "big bad wolf".

The site's critics consensus reads, "Moody and dark, Grimm gives supernatural fantasy a TV procedural sheen.

[43] The Hollywood Reporter's Tim Goodman felt that "[i]t has chills and humor and the ability to take a procedural story and twist it.

"[44] Mike Hale of The New York Times said, "Some of the jokes work, and some of the frights are actually scary, and on a repeat viewing the craftsmanship and attention to detail made more of an impression.

"[45] Mary McNamara of the Los Angeles Times wrote in a mixed review that she preferred other fairy-tale themed dramas, such as ABC's Once Upon a Time, stating that despite a good cast and setting, Grimm puts an "entertaining crime spin on fairy-tale monsters that's a little too pat ... [And] adds up to a nice, moody, entertaining-enough hour and the troublesome question of how interesting this will be by the third episode.

"[46] Daynah Burnett, who reviewed the program for PopMatters, felt "[a]s Grimm grasps for compelling analogues between fairy tales' villains and ours, its stories turn exceedingly literal: wolves urinate in the corners of their lawns to mark their territory, rather than lurk (and mark) in ways less obvious and more culturally meaningful.

The critics consensus reads, "Grimm continues expanding upon its own mythology during a darker, thrilling sophomore season.

), but few are more purely entertaining – engaging, clever, tense, funny, well paced and featuring a remarkably appealing cast as the friends and colleagues who help Nick.

"[51] A press release by NBC on November 11, 2011, stated, "Grimm and Up All Night Are the #1 New Drama and #1 New Comedy Among Top % Gainers Going from Live+Same Day to Live+7.

[76] In January 2025, it was reported that a reboot film is in development at Peacock, with the show's co-creators Jim Kouf and David Greenwalt acting as executive producers on the project.