AS someone who spent his childhood glued to the Time Lord’s adventures, becoming the new Doctor Who was a bit of a scoop for Peter Capaldi, the third Scot to play the famous Time Lord.
In fact, in some ways he felt over-qualified.
“I had to be very patient on set, because there were always a very nice prop guys telling me how to work the Tardis, and I was like, ‘I know how to work the Tardis. I’ve known for a very long time how to work the Tardis. Probably longer than you, so you don’t need to tell me’,” he jokes.
Today, we meet in an underwhelming and stickily-hot meeting room in the production offices of the Cardiff studio, where the much-adored programme is filmed. Just a minute’s walk away stands the very Tardis the actor is chatting about.
Packed with books, and blackboards with phrases like ‘introvert vs extrovert’ scrawled on them in chalk, Capaldi’s Tardis glows under a faint orange light.
Although he’s peaked behind the wizard’s curtain, as it were, and spent some time in the famous blue box, the actor still can’t quite get his head around the fact that he’s the chosen one.
“I’m constantly amazed that it’s me,” says Capaldi, 56, who lives in London with his wife, actress and producer Elaine Collins, and their teenage daughter, Cecily.
“I wake up in the morning and I go, ‘I’m Doctor Who. I’m playing Doctor Who, I’m Doctor Who’. It’s a huge privilege and hugely exciting, and it’s funny, because I’ve known the show since I was a kid.”
Although he hasn’t consistently watched the series as an adult, it has always been part of his life.
“There was definitely a time I grew apart from it, because you reach 17 or 18 and you start getting into sex and drugs and rock and roll and off you go, you leave the programme behind,” he says, grinning.
“I grew up in the Sixties, so I grew up with Doctor Who and The Beatles and Sunday Night At The London Palladium, school milk and bronchitis and smog and all this stuff, so it’s part of my DNA.
“So although one goes away, the prodigal son returns.”
While this prodigal son is obliging and polite, there are still moments when ruminating over the right word, his eyes locked on yours, you momentarily expect Capaldi to launch into a foul-mouthed (and fiercely funny) tirade, as per his The Thick Of It character Malcolm Tucker.
He’s often stopped by fans of the satirical comedy, who ask him to swear at them.
That probably won’t happen with Doctor Who, but Capaldi, who studied art and was lead singer in a punk rock band during his younger years, is aware that this role will likely escalate his global appeal. Worldwide recognition is just one of the things he’s having to contend with; there’s also the “colossal” production of the series before it even reaches screens.
“You can say all you like about read-throughs, that they don’t matter, but when you’re in a room with 250 people and they’re waiting to see what the new Doctor’s like, you’ve got to go for it,” he says.
Viewers, of course, have had to wait until the new series kicked off, on Saturday to find out what the new Doctor is like, but Capaldi revealed that he is a “slightly more mysterious figure”, who “struggles to find himself”.
“He’s different from the others and yet he’s the same,” says the actor, shrugging. “That’s useless isn’t it? It’s basically useless but it’s true.”
He arrived in Victorian London, to find dinosaurs in the Thames and a spate of deadly spontaneous combustions. Previous Doctor Who, Matt Smith, made his departure in last year’s 50th anniversary special, where Capaldi made his first appearance.
But his companion Clara, played by Jenna Coleman, remains, and the first episode of the new series saw the two finding their way with their friendship amid an alien conspiracy.
Whether his performance and the storylines are enough to win over the show’s throng of fans is something Capaldi is feeling philosophical about.
“You do your best,” reasons the actor, who also played Cardinal Richelieu in BBC One’s family action series The Musketeers earlier this year.
“I don’t know whether everyone else will like it or not. It goes out to the world, so we’ll see what happens.”
Mindful that taking on such a popular character will mean aggrieving some fans - somewhere in The Whoniverse - Capaldi has a clever way of putting things in perspective.
“I think the nice thing about Doctor Who is whether people like it or don’t like it, somewhere, someone loves you and will always love you - and the more everyone hates you, the more they’ll love you,” he says with a wry smile. “’He was my Doctor Who’, they’ll say.”
And for the time being, Capaldi loves that Doctor too.
“I feel guilty,” he adds. “Every day is amazing.”
Doctor Who: Into The Dalek Part 2, BBC One, Saturday, 7.30pm