K9 and Company K9 and Company was a proposed television series in the early 1980s . It was intended as a spinoff of " Doctor Who " . Ultimately only a single pilot episode was produced . It aired on BBC1 as a Christmas special in 1981 . The series was to have starred Elisabeth Sladen reprising her role as Third and Fourth Doctor - companion Sarah Jane Smith , with John Leeson returning as the voice of K9 or to be more precise , K9 Mark III . The pilot episode was produced by then - " Doctor Who " producer , John Nathan - Turner , and is significant for being the first televised spinoff of " Doctor Who " . It is the precursor to " The Sarah Jane Adventures " . Although the pilot did not result in a series , " K9 and Company " has had a lasting impact on the character of Sarah Jane and the " Who " franchise . Most significantly , it offered insight into her family history , aspects of which have been used to build her post - TARDIS life in stories across all media . Most Doctor - less Sarah Jane fiction written after 1981 — like " The Sarah Jane Adventures " and the Big Finish Productions Sarah Jane audios , as well as the 2006 " Doctor Who " episode " School Reunion " — use elements first seen in " K9 and Company " to inform their presentation of the character . Overview . The pilot episode was titled " A Girl ' s Best Friend " . It was broadcast on 28 December 1981 . In it , Sarah Jane gained a companion / assistant of her own , her aunt ' s ward Brendan Richards , played by Ian Sears . Brendan was studying computers and additional maths at school among other subjects . The pilot episode began with Sarah discovering a boxed K9 Mark III , a gift from the Doctor . The plot which followed involved a strange mixture of occult spookery and mundanity , with robed pagans chanting " Hecate ! " and the supposed goddess being revealed as a person in a mask . The action occurred in early to mid - December , the last scene on Christmas Day . As a result , " A Girl ' s Best Friend " is the first Christmas - themed " Doctor Who " universe special ( as opposed to a regular episode , such as " The Feast of Steven " in " The Daleks ' Master Plan " ) , predating by a quarter - century the tradition followed by the revived " Doctor Who " series . Many " Doctor Who " fans remember it most clearly for its electronic theme music , composed by long - term " Doctor Who " enthusiast and record producer Ian Levine . Both the theme music and title sequence have been ridiculed . Levine , who was also the unofficial continuity consultant for " Doctor Who " in the 1980s , said in an interview with " Dreamwatch Bulletin " that the music was intended to be an orchestral score , but was instead arranged directly from his electronic demonstration arrangement by Peter Howell ( who also arranged the 1980s version of the " Doctor Who " theme ) without Levine ' s knowledge . In an interview included on the DVD release , John Leeson jokes about being hired to come to the recording studio and being asked to simply repeat the name " K9 " several times . This later was edited into the theme music , allowing K9 to " sing " his own theme song ! Accolades . The viewing figures for the pilot were very strong , but due to a changeover in channel controllers at BBC One , a series was not made . Although previously approved by controller Bill Cotton , new controller Alan Hart disliked the idea . Aftermath . Despite the fact that a full series was never commissioned , the concept of " K9 and Company " was acknowledged within " Doctor Who " itself as part of the show ' s continuity . In the 1983 anniversary special " The Five Doctors " , which featured appearances by many past companions , Sarah Jane makes her entrance accompanied by K9 Mark III ( the presence of whom is not explained for the benefit of those unfamiliar with the spinoff ) . Decades later , " School Reunion " again features Sarah and K9 Mark III , who was replaced with K9 Mark IV at the end of the episode . This in turn was followed by another attempt at a spin - off series , this time successful : " The Sarah Jane Adventures " ( which had four full seasons and a short fifth season due to star Elisabeth Sladen ' s death ) . While K9 Mark IV was on " The Sarah Jane Adventures " , K9 would later have a ( non - BBC ) spin - off of his own with the original K9 returning in a new form . The " Doctor Who " franchise would not attempt another TV spinoff until " Torchwood " in 2006 . Other media . The pilot episode was novelised in the late 1980s as the last in the Target Books series called " The Companions of Doctor Who " . The adventures of Sarah Jane would later continue in audio form as part of a series of licensed " Doctor Who " - related projects made for audio in the early 2000s by Big Finish Productions . Although this series did not include K9 , John Leeson reprised the role for several other Big Finish productions . There was also a K9 Annual dated 1983 . In 1982 , a record was released in the United Kingdom with an A side of the theme music and a B side track called " Shana the Star Dancer " by Phil Wells . In 1983 , it was released in the United States with the same A side , but a B side entitled " The Leisure Hive " .