With the new series of ‘Doctor Who’ debuting on BBC One next Saturday, the current Timelord Peter Capaldi has been opening up about his experiences since he became the 12th Doctor. Speaking to The Telegraph, Capaldi admitted that he doesn’t think he’s quite ‘nailed’ the iconic character yet.

Peter Capaldi Doctor WhoPeter Capaldi returns in ‘Doctor Who’ on BBC 1 next Saturday.

“I don’t feel I’ve nailed it yet – from an acting point of view, I mean,” Capaldi told the newspaper. “I don’t yet feel that I know how to do this. Quite who the Doctor is remains mysterious to me – which is of course as it should be – but one of the biggest challenges that I’ve found, and am finding, is that you have to sort of be able to spin on a penny.”

“You have to be able to go from pantomime to tragedy, from domestic to epic, within a single scene. You have to keep the ball in the air, and you have to remember that ‘The X Factor’ is on the other channel. You have to remember that there are people watching in America, you have to remember that, as much as you want to apply your mature acting instincts, there are actually lots of children watching.”

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“You’ve got to cover all these bases, and make it exciting and interesting too. It’s a great challenge,” the actor added. Capaldi, a life-long ‘Doctor Who’ fan also spoke about what he wanted to bring do his incarnation of the Doctor. “What I wanted to do, I suppose, was remind people of the alien-ness of the Doctor,” he said.

“Doctor Who isn’t a human being, you see. He’s a creature of the cosmos. His social skills aren’t great. He doesn’t care very much if people like or dislike him, because people aren’t his thing, you know?”

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But despite the challenges of playing one of the most iconic characters on TV, Capaldi knows its important to enjoy himself while it lasts. “All this will come to an end, you see,” the actor mused. “It might just be my Scottish melancholia, but the very first day I found out I’d got the job, I started to feel sad that one day I would not have it; that there would come a day, in the not too distant future, that I wouldn’t be Doctor Who any more.”

“One day I’ll just be an overweight has-been, trying to get a meeting with Jenna Coleman [Clara, the Doctor’s companion] and being ejected from a ‘Doctor Who‘ Convention in Bolton for being drunk and disorderly. I mean, this is surely my high point, isn’t it?” ‘Doctor Who’ returns to BBC One on September 19th.