Andrew Cartmel Andrew Cartmel was the script editor for the classic series of " Doctor Who " during its last three seasons . Raised in Canada , he took a post - graduate course in Computer Studies and worked on computer - aided design for Shape Data Ltd ( now UGS Corp ) in Cambridge , England during the mid - 1980s , before he turned to writing and gained an agent on the strength of two unproduced scripts . He also attended workshops run by the BBC Television Drama Script Unit . Biography . In 1987 , Cartmel was hired as the script editor for the twenty - fourth season of " Doctor Who " . He was recommended to the producer John Nathan - Turner by the producer ' s agent , who had seen some unproduced scripts Cartmel had written . Cartmel worked on the programme for the next two years , overseeing the final three seasons of its original run on BBC One . He brought in new writers and took the series in a new creative direction . Although he is not credited with writing any of the serials under his watch himself , he is credited with composing the key monologue delivered by Sylvester McCoy at the end of " Survival " episode 3 — the final episode of the original 1963 - 89 series . The most lasting legacy of this new direction was the " Cartmel Masterplan " , a backstory developed with other writers that restored some of the mystery of the Doctor ' s background and eventually would explain exactly who he was . Unfortunately , although hints were dropped in the last two seasons , the proposed revelations never materialised on screen because the programme was taken off the airwaves in 1989 . Even if " Doctor Who " had not come to an end in 1989 , Cartmel would have left the show ; he had already been head - hunted due to his success there to take over the script editor ' s role on the BBC ' s hugely popular medical drama series " Casualty " . After one season working on " Casualty " in 1990 , Cartmel left the television industry for the rest of the decade . In the 1990s he wrote comic strips for " Judge Dredd Megazine " and " Doctor Who Magazine " and three " Doctor Who " novels for Virgin Publishing in their " New Adventures " series . This series used elements of the " masterplan " as part of their overall arc for the Doctor , particularly the last Seventh Doctor novel , " Lungbarrow " , written by Marc Platt . In 1999 his first original novel , " The Wise " , was published by Virgin ' s short - lived series of new science - fiction novels , " Virgin Worlds " . The same year , he became editor of the science - fiction magazine " Starburst " . His tenure was a short one and he left the magazine in 2000 . In 2001 he returned to television as the script editor on the second season of Channel 5 ' s fantasy / adventure series " Dark Knight " , writing what proved to be the series ' final episode . He also wrote a stage thriller with Gothic overtones , " End of the Night " , which was successfully staged by Long Shadow Productions in the summer of 2003 . In the 2000s he has also returned to " Doctor Who " fiction , writing the script " Winter for the Adept " for Big Finish Productions ' range of " Doctor Who " audio dramas in 2000 , a novella , " Foreign Devils " , for Telos Publishing in 2003 , and the BBC Books novel " Atom Bomb Blues " in 2005 . Cartmel had several other books published in 2005 . " Script Doctor - The Inside Story of Doctor Who 1986 - 89 " is an account of his work on the " Doctor Who " television series . There was also another " Doctor Who " non - fiction book , " " , and he contributed to the charity reference book " " . In 2014 , he began writing comic strip stories for " Doctor Who Adventures " magazine , starting with stories for the Eleventh Doctor and later transitioning into Twelfth Doctor stories . In 2016 , Cartmel wrote a run of DWA comics beginning with " From the Horse ' s Mouth " that gave the Twelfth Doctor a horse - like companion named Jata . Six Cartmel - written Jata comics were published ; due to " Doctor Who Adventures " being " paused " the Jata storyline did not receive any closure . He lives in London and is currently lecturing at Saint Mary ' s College , Surrey .