TV adaptations of popular works of literary fiction are tricky to pull off. When those works are as complex and detailed as Terry Pratchett's Discworld series, it's pretty much impossible. The Watch attempts to get around this challenge by insisting the BBC America show is not an adaptation of the novels in Pratchett's series about the Ankh-Morpork City Watch, but a non-canon narrative inspired by its characters. This has raised alarms with the books' dedicated fans, and they have reason to be concerned. The series adjusts and re-imagines many of the novels' characters and settings (and eliminates others entirely), while creating a story that's a mishmash of at least two of the City Watch-centric books' plots. Yet if this was done in an attempt to appeal to viewers who are unfamiliar with the Discworld series, it hasn't worked. While the show is stylish and quirky and even periodically funny, as a narrative it never manages to capture the imagination.

The show centers on Sam Vimes (Game of Thrones' Richard Dormer), the captain of the City Watch, a jaded drunk who has checked out of life. This is because since he first joined the law-enforcement organization, the city has legalized crime for all intents and purposes. Ankh-Morpork permits anyone to hire another to commit a crime, from assassination to petty theft, as long as the person they hire is a member of a professional guild and they have a receipt for the transaction. As a result, Vimes and his team -- which includes Corporal Angua, a werewolf (Marama Corlett), Constable Cheery, a dwarf who's asserted her gender identity as female by shaving her beard (Jo Eaton-Kent) and Sergeant Detritus, a troll made of rocks (Ralph Ineson) -- don't serve much purpose. That starts to change when several things happen almost simultaneously.

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First, the idealistic and enthusiastic Constable Carrot (Adam Hugill), a human raised by dwarfs, joins the team. Then, the Watch is tasked by Lord Vetinari (Anna Chancellor), the calculated leader of Ankh-Morpork, with finding a library book that was pilfered from Unseen University, which is sort of like a grimier version of Hogwarts. And finally, Vimes notices a man he thought he killed 20 years ago, Carcer Dun (Samuel Adewunmi), is back -- and not only is he alive, he hasn't aged a day.

From there the plot becomes a race to stop Carcer's plan to destroy the city by harnessing the power of a dragon. In each episode of the five provided for review, the Watch team seeks out a new artifact or piece of information to thwart Carcer. Meanwhile, the villain mostly stays one step ahead of them even as he has to adjust in the face of various obstacles. Along the way, the team is joined by Lady Sybil Ramkin (Lara Rossi), a noblewoman who owns a tiny dragon, and a talking sword named Wayne (Matt Berry), and periodically runs into a put-upon, incompetent Death (Wendell Pierce).

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I suspect for Discworld fans this will all come across like big-budget City Watch fan fiction. As someone unfamiliar with the books, I can't claim any personal attachment to any specific part of that story, but even the little research I did made it clear that the show doesn't bear an especially strong resemblance to its supposed source material. The bigger disappointment, however, is despite all those changes, the show hasn't managed to do anything compelling with them. The plot mechanics of the story are on full display, which makes the Watch's pursuit of MacGuffin after MacGuffin feel like forced labor instead of organically motivated action. Furthermore, the reasons for Carcer's activities are turned into a mystery that never comes across as worth solving.

It's difficult to care about the characters too. The actors do what they can with the material they're given, each committing to their characters' specific traits and backgrounds. I especially enjoyed Eaton-Kent's Cheery, whose smart sensitivity is a nice counterpoint to her cynical or naive colleagues. Still, the show is so caught up in maintaining its punk-rock aesthetic and devil-may-care attitude, it never makes anything onscreen feel worth investing in. So while The Watch boasts impressively designed sets, costumes and characters that create a strong sense of place -- even if that place isn't necessarily Pratchett's Discworld -- it has little going for it other than its style.

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 will premiere on Jan. 3, 2021.

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