Of the 253 episodes of "Doctor Who" that were produced in the 1960s, 106 no longer exist in the BBC Television Archives due to an archive purge between 1972 and 1978, during which BBC Enterprises destroyed the only known copies believing them to be of no future value. The BBC stopped destroying episodes in 1978 when this policy came to the attention of the series' fans. From this point the BBC realized the potential commercial and cultural value of the series and audited their archives that same year. The most recent episode to be recovered as of 2006 was a print of the 1965 episode "The Daleks' Master Plan: Day of Armageddon", returned by a former BBC engineer in January 2004. In December 2011, a further 2 episodes were recovered, this time from a former ITV engineer: "Doctor Who" (1963) {Air Lock (#3.3)} (Part 3 of the "Galaxy 4" serial) and "Doctor Who" (1963) {The Underwater Menace: Episode 2 (#4.20)}.
In addition to 106 episodes that no longer exist, some episodes no longer exist in their original format. Four episodes only survive in an edited state - "Checkmate" ("The Time Meddler": Episode 4), "The Celestial Toymaker": Episode 4, "The War Machines": Episode 3, and "The War Machines": Episode 4. Furthermore, eleven episodes only survive in black and white whilst originally filmed in color - "The Ambassadors of Death": Episodes 2, 3, 4 and 7, "The Mind of Evil" (all six episodes) and "Invasion of the Dinosaurs": Part 1. Many of the Jon Pertwee episodes from the early 1970s, made in colour, now only exist as poorer quality NTSC 525-line colour versions recovered from Canada, the original 625-line colour master tapes having been wiped by the BBC in the 1970s, and as 16mm black and white telerecordings which had been kept by BBC Enterprises. For some Pertwee episodes wiped by the BBC, NTSC colour versions were not recovered and they remained only as the 16mm black and white telerecordings for many years. In the early 1990s, three serials ("Doctor Who" (1963) {Doctor Who and the Silurians: Episode 1 (#7.5)}, "Doctor Who" (1963) {Terror of the Autons: Episode One (#8.1)} and "Doctor Who" (1963) {The Dæmons: Episode One (#8.21)}) were restored to colour using the 16mm black and white telerecordings and the colour signal from NTSC domestic recordings to create new master copies on D3 digital tape. "Doctor Who" (1963) {Planet of the Daleks: Episode Three (#10.17)} was restored to colour for the serial's DVD release in 2009 using the colour signal (also known as chroma dots) discovered in the black and white telerecording. All the colour master tapes starring the last four Doctors, Tom Baker, Peter Davison, Colin Baker and Sylvester McCoy have survived intact.
The format of the show's entire run was a series of cliff-hanger adventure serials. Each of the Doctor's adventures would be told across several half-hour episodes, with a cliff-hanger ending each one. Each "season" of the show would be broken into several stories, taking usually 4 to 6 episodes to play out - on-screen, each individual episode would begin with the title of the story ("The Android Invasion", to name one), followed by the story's author, then what episode the story the audience was watching ("Part One", for example). This method of titling wasn't established until late in the third season; prior to that, every episode was given its own unique title. Because of this, there are no 'official' story titles to the earliest adventures, though semi-official ones have been consistently used on DVDs, books, etc.
When the series was syndicated in the US, many stations did not show it in its half-hour long, cliff-hanger format. Instead, a "movie version", made up of all episodes of one adventure, but with the cliff-hanger endings edited out, would be shown. Since the number of episodes used to tell one story would sometimes vary (usually four episodes, but sometimes 6, 7, or only 2), the "movie versions" varied in length. Because of this, many stations showed the movie versions on weekends, in late-night or early-morning slots, where their schedules were more flexible.
On three occasions, past Doctor actors have to returned to the series as the Doctor in stories known as "multi-Doctor" stories, meaning that they feature multiple incarnations of the Doctor. In 1973, the tenth anniversary story, The Three Doctors, saw William Hartnell and Patrick Troughton return to the role alongside Jon Pertwee. In 1983, the twentieth anniversary story, The Five Doctors, saw Patrick Troughton and Jon Pertwee return to the role alongside Peter Davison whilst Richard Hurndall played the role of the first Doctor (William Hartnell, who had passed away some years earlier) and Tom Baker appeared only in footage filmed for a story called Shada (1979), which was abandoned due to strike action. Finally, in 1984 Patrick Troughton reprized his role alongside Colin Baker in The Two Doctors.
Asteroid 3325, a small main belt asteroid discovered in 1984, is named TARDIS after the Doctor's time/space machine.
Many actors have been considered for the role of the Doctor over the years but only Ron Moody has twice declined the role. He was first choice after Hartnell left but refused (as did 'Peter Jeffrey (I)'), and he also turned down the chance again in 1969 when Troughton left. Graham Crowden turned down the role after Pertwee and veteran British comedian Richard Hearne was also considered but rejected for insurance purposes. In the revived version, Doctor Who (UK), Bill Nighy came closest to assuming the role after Christopher Eccleston left but was rejected at the last minute in favour of David Tennant (Nighy amusingly blamed Tennant for being better-looking).
Changes to the cast were a regular fixture of the series - only five of the series' 26 seasons (the 8th, 9th, 22nd, 25th and 26th) did not include an arriving or departing regular cast member. Only two regular characters did not get a departure scene: the character of Dodo Chaplet disappeared halfway through the 1966 serial "The War Machines"; the character Liz Shaw simply did not return after the 1970 season. The departures were explained in dialogue in subsequent episodes. Actors Mary Tamm and Colin Baker did not get leaving scenes - their characters (Romana and the Doctor, respectively) returned at the beginning of the following season played by different actors. However, their characters belonged to a race whose appearance, it had already been established, would frequently change thus making the change of actors easy to explain.
Jon Pertwee had incredible difficulty learning some of the technobabble that the Doctor is famous for, so the crew hid cue cards in the set.
"The Celestial Toymaker" received complaints that the character Cyril was based on the Billy Bunter character created by Frank Richards (III), whose lawyers were incensed. The BBC issued a statement saying that Cyril was merely a Bunter-like character.
The original pilot episode was rediscovered in 1978 in a mislabeled film can. After an archive purge by the BBC between 1972 and 1978, the film survived by chance and was originally thought lost forever.
The BBC owns the copyright to the design of the Police Box as used as the design for the TARDIS. It was bought from the Metropolitan Police.
The longest running sci-fi series ever made for television.
The pilot episode of the series would have been the first transmitted edition had it not been remounted on the recommendations of BBC executives. It has been shown on television in the UK once, in 1991, and remains the only surviving episode from the 1960s held in its original unedited format.
When it became clear that failing health was affecting his performance and relationship with the cast and crew, William Hartnell, the first actor to play the Doctor, was asked to leave the show. Rather than cancel the successful series, the writers came up with the Doctor's ability to regenerate his body when he is near death, which allows for the smooth transition from one actor to another playing the role.
Originally, the Doctor's time machine, the TARDIS, was to have a different appearance in order to blend in wherever and whenever it materializes due to its "chameleon circuit." However, it was decided that this constant changing of a regular prop would be too expensive. So, it was decided that the circuit would be permanently disabled due to the TARDIS' age, thus retaining the appearance of a 1963 Police Callbox.
The name of the Doctor's time machine, the TARDIS, is short for "Time And Relative Dimension In Space". In later serials, this was changed to "Time And Relative Dimensions In Space" (Dimensions in plural), but the series revamp (2005+) has reverted to the singular usage.
Ian Marter, who played Surgeon Lt. Harry Sullivan, also wrote the novelizations of several Dr. Who stories.
As William Hartnell's illness progressed, he started to have memory problems and often forgot his lines. Many unusual ad libbed lines in place of those scripted were passed off as part of the Doctor's character.
The distinctive TARDIS sound effect is officially classified as a piece of music and was created by rubbing the bass strings of a piano with a key.
Two reasons are given for the first episode of the first series series being repeated the following week: a) it aired the day after John F. Kennedy's assassination and as a result drew lower than expected audiences. b) there was a widespread power failure and the episode was not seen nationwide.
Jon Pertwee was fond of using the phrase "reverse the polarity" in his dialog, so the writers made sure his incarnation of The Doctor said it frequently. The most common use was the technobabble sentence "Reverse the polarity of the neutron flow", which, due to its popularity with fans, was also used occasionally by later Doctors.
The series was originally devised as an educational program for kids, with co-creator Sydney Newman having no intention of featuring "bug eyed monsters." The first episodes featured cavemen. But when the Daleks were introduced, the attitude of the program was forever changed. Even so, the series continued to alternate between science fiction and purely historical stories for several seasons.
The Beatles make a cameo appearance on a 1965 episode called "The Chase", in which they're seen on a time scanner performing "Ticket to Ride" on "Top of the Pops" (1964). Originally, the plan was to have the actual musicians appear as old men, but the idea was vetoed by Beatles' manager Brian Epstein. Ironically, the live footage used in the episode is all that remains of this performance, as the episode of Top of the Pops it was taken from was erased.
During the 1970s, series star Tom Baker attempted to have a feature film made titled "Doctor Who Meets Scratchman", which would have co-starred Vincent Price.
The series was in part inspired by the British The Quatermass Experiment (UK) TV serials of the 1950s. In 1988 the show paid homage by referring to Quatermass in the 1988 episode "Remembrance of the Daleks." It is also implied that this episode takes place the day "Doctor Who" made its debut on TV. Quatermass creator Nigel Kneale turned down offers to write for Doctor Who, revealing in subsequent interviews that he disliked the concept of the series and regarded it as unsuitable for children to watch. Nevertheless, several Doctor Who stories were influenced by Kneale's stories.
Although a number of spin-offs were considered throughout the course of the programme (including vehicles for the Daleks, for UNIT, and for the Jago and Litefoot characters from the Tom Baker serial "The Talons of Weng Chiang"), only one was ever produced as a pilot. This was K-9 and Company: A Girl's Best Friend (1981) (TV), aired initially as a Christmas special. Although it fared well in the ratings, the BBC decided not to proceed with a series. Ironically this featured ex-companions Elisabeth Sladen as Sarah Jane Smith and John Leeson as the voice of K9 - both would return for the altogether more successful 21st Century spin-off The Sarah Jane Adventures (UK).
When the script called for him to recite coordinates to program the TARDIS, Tom Baker would sometimes rattle off a string of digits that was actually the telephone number to the "Doctor Who" production office; no one ever caught on.
The word "Dalek" became so familiar to British audiences that it was added to the Oxford English Dictionary.