A lot of Terry Pratchett fans aren’t too happy with the BBC’s new series The Watch. The show, which is based on the author’s Discworld series of books, was maligned by would-be viewers as soon as the first trailer was released and has since airing received negative reviews from critics and viewers. The discontent might seem a little extreme at first, especially since on-screen adaptations are seldom exactly like the source material, but the complaints might be justified in this situation.

Dubbed as a “punk rock thriller,” The Watch borrows only a few aspects of the books upon which its based, which include the beloved Guards! Guards! and Night Watch. Set in the fictional city of Ankh-Morpork, where crime has been legalized, The Watch is ultimately a new plot that follows the Ankh-Morpork City Watch as it tries to save its home from the brink of disaster. However, the on-screen version of  Ankh-Morpork is much more modern ands feels incredibly dissimilar to its namesake in the books. In keeping with that style, the Watch's look ends up getting modernized, with officers wearing regular jackets rather than armor.

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However, the changes go deeper than just the aesthetics, as the novels' main characters have been altered in major ways. Fan-favorite Cheery Littlebottom, for example, is no longer a dwarf and is instead a human, which makes for a rather unnecessary species swap; Lady Sybil Ramkin is a vigilante instead of an animal-loving, upper-class recluse; and Angua von Überwaldhas has ditched her long blonde hair in favor of a shorter style to match her new angst-filled personality, which is a far cry from Pratchett’s more complex depiction of the character. A variety of characters that featured prominently in the Discworld novels also didn’t make it to the series -- like original City Watch members Nobby Nobbs and Fred Colon, as well as troll officer Detritus. From there, The Watch changes Sam Vimes' backstory and now has him having grown up at the same orphanage as the villainous Carcer Dun, which changes a number of major themes and personality traits.

Loyal Pratchett fans expressed their displeasure with these changes to the source material, including his daughter, Rhianna Pratchett. Prior to the The Watch's release, Rhianna shared her thoughts about the show, saying, “It’s fairly obvious that The Watch shares no DNA with my father’s Watch. This is neither criticism nor support. It is what it is.” Writer Neil Gaiman, who collaborated with Pratchett on the novel Good Omens, has also sided with disgruntled viewers, saying on Twitter, "It’s not Batman if he’s now a news reporter in a yellow trenchcoat with a pet bat.”

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While these changes have added some diversity to the source material, the depth of the changes to Pratchett's beloved works have definitely upset many of those who love the writer's work. Although it's entirely possible The Watch may one day be remembered more fondly than the current reception to it, the backlash to the series started early, and no doubt hurt the show's prospects for success.

The Watch is executive produced by BBC Studios' Hilary Salmon (Luther) and Phil Collinson (Doctor Who). The series, which will run for eight episodes, is written by Simon Allen (Das Boot). It stars Richard Dormer, Anna Chancellor, Lara Rossi, Ingrid Oliver, James Fleet, Marama Corlett, Sam Adewunmi, Jo Eaton-Kent, Adam Hugill, Hakeem Kae-Kazim, Ruth Madeley, Bianca Simone, and Ingrid Oliver. The Watch airs Sundays at 8 pm ET/PT on BBC America.

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