Harry Potter star David Bradley plays the very first Doctor William Hartnell in An Adventure In Space and Time (BBC2, Thursday) a special drama which tells the unlikely story of how the well-loved show was born 50 years ago.
We caught up with him to talk about his Doctor Who memories and how he spent a month watching the show in preparation for the role!
How much does it mean to be doing this as part of the 50th anniversary celebrations?
"It means a lot! You want to convince the audience that you could not only be Doctor Who, but also William Hartnell. Bill was a very highly regarded actor with an enormous CV well before Doctor Who began in 1963, so I felt quite a responsibility to do him and the legions of fans who remember him justice."
We hear that Waris Hussein (who directed the first episode of Doctor Who) was present during filming?
"He was watching on the monitor while we filmed one of the first scenes and Mark Gatiss (who wrote this one-off special) told me he saw him welling up a bit. I was very touched and very gratified by that because Waris was there at centre of it when it all began and maybe it brought back a lot of memories for him."
The first pilot they filmed was rejected by the BBC bosses...
"Yes it was. I watched the rejected pilot and the one that was broadcast and I was amazed by the ease with which Bill adjusted his performance from being 'too nasty' to being more playful. It was even more impressive because he and the rest of the actors didn't have the benefit of doing retakes!
"We all forget our lines from time and we just have another go. But then they were only allowed four tape stops and that included set changes, so they didn't have much time to do retakes over minor script diversions!"
How important was it for you to play William Hartnell the man, as well as William Hartnell as the Doctor?
"That was crucial. I wanted to get his voice right as well, because he put on a slightly different voice for Doctor Who. Not many people know what Bill actually sounded like, but I found a clip of him in a dressing room doing panto a few years after he left the show and that's the only one I have of him actually being himself. But I've had the benefit of listening to his screen voice over and over, so I've been able to study every inflection and every movement - because there are lots of people who'll be looking out for that!"
He was quite reluctant to take the part at first wasn't he?
"Initially he would have been very attracted to it, but when he heard it was a children's show I don't think he was so keen. At the time children's TV was Muffin the Mule and Andy Pandy, so you can understand his concerns because he'd had a great film career. But once he met the team I think he realised it was going to be quite a career departure for him."
Did you know you'd be doing this while you were filming Doctor Who episode Dinosaurs on a Spaceship last year?
"I had no idea! I was stood on the roof of the National Theatre in the pouring rain during the Queen's Jubilee and Mark came told me he was doing this and would I like to play Bill? I was so excited at the thought of it!
"I met Mark just before Christmas to talk about it and then I had a month or so to catch up on the DVDs and soak it all up. There's endless stuff on YouTube as well, which shows how popular the show was even back then."
Did you get a chance to talk to the original cast and find out what kind of man Bill was?
"I spoke to Waris and Carole Ann Ford (who played the Doctor's first sidekick Susan) and both said he could be absolutely charming and great fun to be around at times and at others - the opposite! He was a complex man I think.
"His background and his upbringing had a lot to do with that, but he was a consummate actor, an absolute perfectionist and he expected the same of others around him. It's only when he felt other people didn't have the same commitment to the project or were flippant about it, that he would get upset."
Do you think this drama might inspire any young Doctor Who fans to go back and watch the earlier series?
"I hope so because Bill was a terrific screen actor and even with the limitations they had upon them at the time, his performance shines through. I was never sure who my favourite Doctor was, but now I think it's Bill.
"All the subsequent actors who have played it have defined it for themselves, but he defined it for the first time. He had no template to work from, he had to find this character. I think it rejuvenated him in many ways and I think it hurt a great deal when he had to give it up."
You were 21 when Doctor Who started, did you watch the first episode?
"I remember the show when it started, but at that age I was more interested in going down the pub on a Saturday night! I watched some of the John Pertwee episodes and when Tom Baker played the Doctor my good friend Louise Jameson was his sidekick so we watched every episode!
"Then it went off the air for quite a while and I never picked it up again until Matt Smith started doing it, which was handy because I did that episode last year. I love what he does with the Doctor, he's got that right level of curiosity which was one of the main driving forces behind the character. Matt has that and the right level of eccentricity and fun, but I'm sure Peter Capaldi will be just as good when he takes over."
