Pearl Mackie was ordered not to watch 'Doctor Who' by programme bosses.
Peter Capaldi and Pearl Mackie
The 29-year-old actress has been cast as the Time Lord's new companion Bill Potts in place of departed Jenna Coleman but had rarely seen an episode of the show before she joined the sci-fi series and was keen to brush up on her knowledge.
However, showrunner Steven Moffat and executive producer Brian Minchin advised her to retain her ignorance in order to retain a freshness and innocence to her character, who will feature opposite Peter Capaldi in his final series as the Doctor.
She told SFX magazine: "It wasn't really on when I was a kid.
"I watched some of the new series when it first came out but I was 16, so I was trying to spend as little time at home as possible! So it's quite new to me as well as being new to Bill.
"I think it's stood me in quite good stead in terms of my approach to [playing Bill].
"I talked to Steven and Brian after I'd got the job - I was like, 'Look, gimme the back catalogue, let me watch it all!'
"I initially planned to watch all of Peter's stuff with Jenna, so I could see what he was like as a Doctor, and they were like, 'Don't watch it, because she doesn't know anything about that, and actually what you're bringing to it is a really nice kind of freshness. What you're doing is working'."
And Pearl was glad she took the advice as it made her first day filming in the Tardis even more exciting.
She recalled "Oh, it was amazing.
"I think the first time was the day we were shooting the scene where Bill first goes onto it as well. It's really nice that I'm experiencing that at the same time as her. No acting required, really. I'm just like, 'Oh, this is cool!' "
'Doctor Who' returns to BBC1 on April 15.
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