Jodie Whittaker feared she had “done it all wrong” when she first started playing the Doctor.
The actress, 38, made her debut as the Time Lord in 2018, taking over from Peter Capaldi.
She tells BBC Radio 6 Music that when she first watched Capaldi in the role she feared she had made a mistake.
She said: “When I saw the episode, where Peter’s Doctor regenerates into myself, we were midway through shooting… I hadn’t watched it to try and give myself that freedom to step on set.
“And then when I watch that, I was like, ‘Oh my God, I’ve done it wrong. I’ve done it wrong…’.
“They said, ‘No… you aren’t supposed to be doing what someone else did’.
“But,” Whittaker added, “all the energy of the Doctor and all the references and the Whovian kind of pearls are in there.
“And you then take it and run with it. And actually it’s much more freeing.”
She also told Doctor Who fans that the Christmas special would be “definitely worth the wait”.