Doctor Who actors come to the series with various levels of existing knowledge, from superfans like David Tennant and Peter Capaldi to relative newcomers to the mythos like Matt Smith or Christopher Eccleston.

However, it’s rare that series leads are actively encouraged to avoid watching earlier episodes of the sci-fi series – at least until brand-new companion Pearl Mackie (playing Bill Potts) stepped onto set.

“It wasn’t really on when I was a kid,” Mackie told SFX magazine while explaining her lack of Who knowledge. “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.”

Of course, once Mackie was cast she was keen to get stuck into the back catalogue of New Who – but then she received the surprising advice to continue avoiding it, from none other than series showrunner Steven Moffat and executive producer Brian Minchin.

“I think it’s stood me in quite good stead in terms of my approach to [playing Bill],” Mackie said. “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’.”

In other words, her lack of Who familiarity was just a time-friendly form of Method acting – something which also aided Mackie on her first day in the Tardis.

“Oh, it was amazing,” she recalled.

“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!’”

All in all, then, it’s clear that no experience is sometimes good experience. We’ll remember that one for the next job interview.

Doctor Who returns to BBC1 on Saturday 15th April