Simon Allen, showrunner for the upcoming BBC America series, The Watch, thanked cast and crew in an Instagram post after wrapping on shooting. But fans are angry that Allen left out one rather important contributor amongst his words of appreciation: Sir Terry Pratchett.

Posting an image of the final shooting slate, Allen commented "Saturday. Somewhere in a distant, second hand set of dimensions, in an alternate trouser leg of time... five years ago next Wednesday I wrote the first line of #thewatch script. Tonight we wrap. A miracle in a world of closed doors, minds, borders and hearts. Ridiculously exciting news to announce in a few weeks at #NYCC" and followed it with an enormous list of various cast and crew members involved with the production. But there was no mention of writer Pratchett who created the Discworld universe in which The Watch is set.

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In response, Discworld fans left reams of angry comments such as "That's probably the quickest I've seen anyone alienate an audience...", "No mention of Terry Pratchett? Shame." and "What about #TerryPratchett? You know, the man who actually CREATED the Discworld and the Watch?" Comments on the post have since been stopped.

The Watch is a fantasy police procedural series set around the Ankh-Morpork City Watch from the Discworld series of comic fantasy novels. Though this series is set in the Discworld universe, it's not a direct adaptation of any of Pratchett's novels, instead using existing characters and concepts rather than storylines. The cast includes Richard Dormer (Game of Thrones) as Commander Sam Vimes, Ingrid Oliver (Doctor Who) and Hakeem Kae-Kazim (Black Sails).

Originally published in 1983 with the first book The Colour of Magic, Discworld has spawned  a further 40 novels and sold over 80 million copies worldwide. The first adaptation was an animated series by Danger Mouse creators Cosgrove Hall and live action adaptations of The Colour of Magic, Hoggfather and Going Postal were produced by Sky from 2006 through to 2010.

The Watch is set to premiere on BBC America in 2021

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Source: Simon Allen/Instagram