The range of how the show altered over those 10 years, from its original inception as historical, educational adventures with no bug eyed monsters, up to Pertwee in a Venusian Karate mind fight with Omega is massive. Going back and rewatching some of the first Hartnell stories can be quite a shock to the system. Of course, not only are they in black and white, but the pacing is so utterly different to later eras, with everything moving at a much slower, considered pace. The emphasis of the educational aspects, with the attempts to keep pure historical adventures in focus is I admit, a reason I sometimes struggle with Hartnell stories. More than any other era, I tend to feel they are best digested in their original format: watch a single episode, and then walk away for a bit before coming back to the next one. It is perhaps little surprise that the show eventually moved away from the pure historical stories to focus on the aliens and monsters, but even to this day it sometimes feels like something’s been lost and there’s scope for the Doctor to have a monster-light story.
Of course, its well documented how the Doctor of those early episodes was a far different character. Much more interested in his secrecy in the first episode, he’s clearly not a fan of Susan’s desire for a settled, normal life in attending Coal Hill school. A more sinister, untrustworthy figure, the emphasis is far more in Ian, and later to a lesser extent Stephen, to be the hero of the piece. A stark contrast to Pertwee’s more action-oriented Doctor. Discovered by Ian and Barbara, the Doctor’s first thought is to kidnap them, to prevent his and Susan’s secret being revealed. However, this contrasts nicely with the second story, where we see that wanderlust and excitement that would later inform so much of the character with his enthusiasm to explore the Dalek city (albeit even here his duplicitous actions land the team in a heap of trouble)..
Over the course of the first series the more sinister aspects to the Doctor of course are chipped away at, through his relationships with Susan, Ian and Barbara, leaving the more heroic character we’re familiar by the time Daleks invade the Earth.
Then, as illness took its toll on William Hartnell, a brave decision was made, and the Doctor regenerated. Not simply recast, but a whole new take on the lead character, in many ways almost new character, but with that desire to help those in trouble and that wanderlust to see the universe reminding us that this was still The Doctor. It remains a great shame for the show that the destruction of episodes has hit Patrick Troughton’s era harder than any others. Many actors will point to him as their favourite in the role, and its no surprise. Troughton’s incarnation ran with the idea that his Doctor was unassuming, unthreatening, a buffoon. And then his eyes would harden, and you’d see that razor sharp intellect lurking in the background. Its a take on the character that would inform several of those to follow, most notably Matt Smith.
At this point in the show, the base under siege format would become a favourite, as the Doctor and his companions would arrive in a suitably enclosed area, meet a core cast of characters, and then do their best to save them from the Ice Warriors or, more likely, the Cybermen. And as this move towards invading monsters solidified, and the Doctor returned to modern day Earth with a little more frequency, the groundwork was laid for a very different incarnation of the whole show.
And what a change it was. Now exiled to Earth with the TARDIS disabled, the previously anti-establishment figure became scientific advisor to UNIT. Now at home raiding the wine cellar of Sir Reginald Styles the Third Doctor seems light years away from his past incarnations. But that said, Jon Pertwee made it work. Playing against type, and playing the role dead straight, he manages to toe the line in the character well. While he enjoys an increasingly cosy relationship with UNIT, its setup well by the antagonism of series 7 often finding the Brigadier and the Doctor at loggerheads. While they manage to build a working relationship as they gain respect for one another, the Third Doctor still often finds himself at odds with many of the authority figures he runs across (of course, it helps that many of them are portrayed as self-serving idiots). The Pertwee era would also foster the idea of the UNIT family, with the Doctor no longer just being joined by a few companions, but also have entire supporting cast. An idea that would seem to inform more recent series with the likes of Rose, Martha and Donna’s families making frequent appearances.
1963 to 1973 would see the show going through some of the biggest changes it would face. Despite losing core characters, changing production teams and the main character going through several regenerations, the show would endure. Despite moving from a historically based time and space adventure series to one that was Earthbound and set in (vaguely) the present day, the show continued from facing the axe to being more popular than ever. Something about Doctor Who had grabbed the audience no matter what changes it faced. It had been established as a show that wouldn’t go away. And its biggest star, had yet to be cast.