David Bradley on returning to play the First Doctor: "All subsequent Doctors owe a lot to William Hartnell"

The renowned actor first played the role in 2013's An Adventure in Space and Time, which explored the creation of the long-running series, in which he portrayed both Hartnell and the late actor's incarnation of the Doctor.

Bradley made such a strong impression on fans that he was invited back by writer Steven Moffat to play the First Doctor in two episodes of Doctor Who, both of which aired as part of Peter Capaldi's stint on the show.

As he prepares to return to the role once again for Time Fracture, Bradley has hailed Hartnell's "total dedication" to Doctor Who in an interview on the show's official YouTube channel.

"He laid the template," Bradley said. "All of the other subsequent doctors, they all owe a lot to William Hartnell. As it was, it started this phenomenon."

Bradley went on to reveal that he never expected to return to Doctor Who after his first appearance on the show, which saw him play an entirely unrelated character named Solomon in 2012 episode Dinosaurs on a Spaceship.

He continued: "When that finished, I thought 'well that's my Doctor Who experience, you only do it once'. Little did I know that Mark Gatiss had me in my mind for Adventure in Space and Time. It was a gift, I just said yes."

Bradley will co-star opposite John Barrowman in upcoming live event Time Fracture, billed as an "immersive experience", which he believes could convert even non-believers.

He added: "I could just see it taking off and being something special. It may attract people who may not be Doctor Who fans, but if they are not Doctor Who fans when they go in, they certainly will be when they come out. I just think it's going to be quite an amazing experience."

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