Terry Pratchett

Terry Pratchett was an author of whom Dudley Jackson was "a devotee". There was not a single book of his that he had not read. (AUDIO: The Eternal Summer) Izzy Sinclair was another fan, once asking the Eighth Doctor why they couldn't visit somewhere like Pratchett's Discworld. The Doctor replied that he'd been there, and it was "flat". (COMIC: Fire and Brimstone) Rory Williams tried to read a Terry Pratchett book on a beach on Drago 14 during his and Amy's honeymoon, but it was dissolved by a roving acid-spitting land squid, and he was unable to get a replacement in the town as, by this point in history, the book had been out of print for nearly four hundred years. (PROSE: Honeymoon Horrors)

Behind the scenes

 * Sir Terry Pratchett also wrote the introduction to Behind the Sofa: Celebrity Memories of Doctor Who. All profits from the book were donated to Alzheimer's Research UK, a charity he often supported due to suffering from dementia himself.
 * The first Discworld video game based on Pratchett's work feature voice acting by Jon Pertwee.
 * In the video game Discworld 2 the "Travelling Shop" disappears and reappears in various locations throughout the map accompanied by the sound effect of the Doctor's TARDIS.
 * Good Omens, co-written by Pratchett and occasional Doctor Who writer Neil Gaiman, was made into a TV series, starring David Tennant as Crowley.