Trivia: In case you've ever wondered why everyone in the universe speaks English, Time Lords have the ability to telepathically understand and speak any language they hear and they're able to share this ability with their companions. (As for why everyone in the universe has a British accent, this can be put down to the fact that the Doctor is an Anglophile.).
Trivia: Throughout the whole of Doctor Who, the original series and the new series, the Doctor only refers to himself as 'Doctor Who' once - and this was a mistake by William Hartnell, who was getting frail. The end credits originally listed the actor playing the Doctor as 'Doctor Who', but this later changed to mainly using 'The Doctor'.
Trivia: As mentioned elsewhere, the Doctor regenerated eight times (out of a possible twelve) in the classic series. Here is a short summary of the regenerations, in order of when they happened: First Doctor (William Hartnell) - weakened in a battle with the Cybermen ("The Tenth Planet"). Second Doctor (Patrick Troughton) - forced regeneration when he was exiled to Earth by the Time Lords ("The War Games"). Third Doctor (Jon Pertwee) - radiation overdose ("Planet of the Spiders"). Fourth Doctor (Tom Baker) - fell off Jodrell Bank radio telescope walkway ("Logopolis"). Fifth Doctor (Peter Davison) - poisoned with Spectrox Toxemia ("The Caves of Androzani"). Sixth Doctor (Colin Baker) - the Rani's hijacking of the TARDIS using a navigational guidance system distorter caused enough damage to fatally injure the Doctor ("Time and the Rani"). Seventh Doctor (Sylvester McCoy) - shot by hoodlums in San Francisco, then dies on the operating table (1996 television movie). For the regenerations of the Eighth Doctor and beyond, see the new series.
Trivia: In 1972, the BBC began a "purge" of its archives to save costs, and amongst the shows selected for disposal were all 268 black-and-white episodes of Doctor Who first broadcast between November 1963 and April 1969. Since 1978, cast, crew, and fans of the show have recovered many episodes tagged "missing believed wiped." 97 of the 268 episodes have not been found.
Trivia: Throughout Doctor Who, and in many of the books about the show, there is a discontinuity about what TARDIS stands for. Some people say it is Time and Relative Dimensions in Space, whereas Susan Forman, in the first episode, "An Unearthly Child", says it stands for Time and Relative Dimension In Space (no s at the end of Dimension).
Trivia: Ridley Scott was the man originally contracted to design The Daleks, but proved unavailable. Raymond Cusick was then given the task. According to the book Doctor Who: The Early Years (1986), Cusick was given just one hour to design The Daleks.
Trivia: Of all the actors who have played the Doctor, Colin Baker is the only one to have been fired from the role.
Answer: In 'The Five Doctors', three separate Cyberleaders are definitely used. So it's likely that Cyberleaders are like unit commanders, of which a fair-sized army might have several.
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