In the long history of Doctor Who, there have been many casting choices - and some that didn't quite happen.
1. Hugh David
In another example of how her influence shaped Doctor Who, producer Verity Lambert opted for the veteran actor William Hartnell as the Doctor, turning down Hugh David, aged 38, who had been encouraged to offer to originate the Doctor’s role by Rex Tucker, a personal friend who was a member of the production team back in 1963. David went on to direct an episode each of the show’s fourth and fifth seasons.
2. Geoffrey Bayldon
If ever there was an actor more ironically intertwined with the part of the Doctor than anyone, that would surely be Geoffrey Bayldon, who was suggested for the role after Verity Lambert had said no to Hugh David. Bayldon, however, didn’t want to make the commitment to the part that would be required, and didn’t want to be stereotyped as an ‘old man’. He was then offered the part again when producers were seeking a replacement for Hartnell, but turned that down.
Later, Bayldon accepted the part of Catweazle, a wizard from the 11th century who suddenly finds himself in the 1960s and went on to be famous for that role.
He also appeared as the Crowman, in Worzel Gummidge, which starred Third Doctor Jon Pertwee.
Bayldon appeared in a supporting role as Organon in Doctor Who’s seventeenth season. Then years later he finally took on the mantle of the Doctor -an alternate-universe Doctor in the Doctor Who Unbound audio plays.
The real irony is that, at 80 years old when the second of his two episodes aired, he was and remains the oldest actor to ever play the Doctor.
3. Catherine Zeta-Jones
In the 1980s, when Doctor Who was experiencing its most serious ratings slump, Sydney Newman, the show’s original creator, suggested reviving audiences' interest with a female lead. Newman wanted to temporarily bring back Patrick Troughton as the Second Doctor and then regenerate the Doctor in female form. His original letter to the BBC stated:
At a later stage Doctor Who should be metamorphosed into a woman. This requires some considerable thought – mainly because I want to avoid a flashy, Hollywood Wonder Women because this kind of heroine with no flaws is a bore. Given more time than I have now, I can create such a character.
Actresses considered included for this new Doctor included established talents Frances de la Tour, Joanna Lumley, and Dawn French. The BBC rejected Newman’s proposal, as we know.
Catherine Zeta-Jones, however, was briefly considered as David Tennant’s successor for the part in 2010.
4. Bill Nighy
Bill Nighy also refused the role of the Doctor, as he didn’t want the media scrutiny that he felt would come with it. Nighy appeared in Doctor Who in 2010 as Musée d’Orsay curator and Vincent van Gogh enthusiast Dr. Black. Nighy has never specified at what point he rejected the role.