Barry Letts Barry Letts is perhaps best known as the producer of " Doctor Who " during Jon Pertwee ' s tenure as the Doctor . A former actor , he also had considerable directorial experience . Letts made cameo appearances in several Pertwee - era episodes . Before " Doctor Who " . For years before entering the producing field and being put in charge of " Doctor Who " , Letts worked as a film and TV actor . His earliest credit listed in the Internet Movie Database is a 1943 film called . He appeared in numerous UK TV series , including , " The Black Arrow " , " Z - Cars " and . A foreshadowing of his later career occurred when he guest - starred on two series created by Sydney Newman — and . Newman would later create " Doctor Who " . Impact on " Doctor Who " . His influence ran deeper than the average producer of " classic " " Doctor Who " , as evidenced by his wide - ranging credits . He was the only executive producer of the 1963 version of the show who was not also the Head of Drama Serials or Series , overseeing the work of John Nathan - Turner ' s first year as producer and Tom Baker ' s last year as the Doctor in 1981 . He was the only producer of " Doctor Who " to also serve as a director . He also held a number of uncredited positions in the show , varying from uncredited acting jobs to writing . In this last capacity , he paired with Robert Sloman . As the person who cast Tom Baker as the Doctor , commissioned Baker ' s first year of scripts and significantly advanced Robert Holmes ' career as a " Doctor Who " writer , he also had a profound , but sometimes under - appreciated , impact on Philip Hinchcliffe ' s time as producer . With Terrance Dicks , Letts is also generally seen as the effective co - creator of the Master , Sarah Jane Smith and Harry Sullivan . His contribution to the casting of these characters was especially diligent . He felt it his duty to be on the look - out for suitable actors to replace companions during his time as producer . He kept meticulous records of many actors , on the off chance that one might be required to play a companion . Elizabeth Sladen was about the two hundred - fiftieth actor whose details he had recorded . ( TV : " The Hand of Fear " ) He was so taken with Ian Marter ' s qualities that he twice gave the actor the chance to become a series regular . ( DCOM : " Carnival of Monsters " ) Letts is also credited with introducing certain themes that later appeared in " Doctor Who " . He was the first writer to insist upon including and Buddhism — later seen in stories like " The Seeds of Doom " and " Kinda " — in scripts produced on his watch . Although Letts ' s final formal screen acting credit was in 1966 , he had an uncredited cameo as a train passenger in episode six of " Doctor Who and the Silurians " . ( DWM 222 ) He also provided a Shutdown voice in episode seven of " Inferno " ( DWM 305 ) and a police radio voice in episode two of " Planet of the Spiders " . ( DWM 314 ) Outside the world of televised " Doctor Who " , he was the first writer of " past Doctor " adventures on audio , predating the rise of Big Finish Productions audios by half a decade . He also contributed to the Target Books range of television novelizations and adapted his own radio dramas . Interestingly , his adaptation of " The Paradise of Death " was the final book released by Target before their license passed to Virgin Books . He also wrote a couple of novels for the BBC Past Doctor Adventures range . He was a frequent contributor to the BBC DVD range . While he unsurprisingly appeared on commentaries of stories which he had produced , he also came to be used as a general " authority " on the classic series . He appeared in front of the camera as himself in many bonus documentaries . He was sometimes seen on DVDs of serials in which he had no formal role , as when he was part of a general retrospective on Sarah Jane for " The Hand of Fear " . His autobiography , " Who and Me " , was released in November 2009 . Letts had been scheduled to make public appearances promoting the work . However , he died on 9 October after a long battle with cancer . " The Waters of Mars " was dedicated to his memory .