Peter Capaldi And Pearl Mackie On Why The New ‘Doctor Who’ Companion Should ‘Challenge’ The Time Lord

Pearl Mackie is having fun. When BBC affiliates announced the then-28-year-old actress as the new Doctor Who companion in April, they accompanied the fanfare with a two-minute scene featuring her, Peter Capaldi’s Twelfth Doctor and a bunch of Daleks. In the clip, the pair race through the halls of an unknown ship, avoiding capture and death while Mackie’s character, Bill questions the Time Lord incessantly about his iconic enemies.

“What’s a Dalek?” Realizing he’s dealing with a new companion, the Doctor grows impatient and says, “Never mind. It’s a Dalek.” Frustrated, Bill criticizes his non-answer and repeats the question. “Well that’s not explaining! That’s just saying a word. What’s a Dalek?” What the Doctor describes as a “tank” subsequently confronts them, but all Bill can do is poke fun at its “suckers” and annoy her host with more questions.

Doctor Who has lacked this kind of pervasive, meta-humor in recent years, and it’s evident from his onscreen interactions with Mackie that Capaldi is loving every minute of it. The same can be said for the now-29-year-old performer after we chatted with her, Capaldi, showrunner Steven Moffat and executive producer Brian Minchin at the 2016 New York Comic Con in October. A stage actress whose recent foray into films and television include the Martin Freeman-starring Svengali and the medical soap opera Doctors, Mackie didn’t yet know what to make of the convention. But when it came to discussing her new role, she knew precisely what she was doing.

“She’s a bit of a challenge,” says Mackie. “I think that’s why he likes her, because she doesn’t necessarily react in the way he expects her to. She’s not predictable and very sharp, and he’s interested in the way she reacts to new information. That’s one of the first draws between them. However, she’s obviously fascinated by him and the way his mind works, as she’s never met anyone quite like him.”

Capaldi couldn’t agree more, saying what interested him most about Bill was that she came “from a perspective we haven’t seen for awhile.” Basically, the new companion “has nothing whatsoever to do with the Doctor Who universe. Everything in the show is brand new to her. I think that’s very invigorating for us, as it means we have to retell — or tell afresh — the whole story. We have to explain what all the bits and pieces are. Bill never quite reacts to it in the way the Doctor expects her to.”

The 58-year-old star of The Thick of It, Armando Iannucci’s British predecessor to Veep, was especially drawn to the opportunity both Mackie and the Bill character presented. Mainly, that Mackie and Bill’s arrival would let Capaldi breath new life into his third season as the Doctor while contending with their outsider’s perspective.

“Any new character that enters a scene in a drama actually creates a new version of the other characters, because we respond differently,” explains Capaldi. “The Doctor responds differently to Bill than he would to, say, Clara. That means I have to find new ways of doing that character. I have to go to a new place with him. That’s always exciting for me, because the one thing you don’t want to do in a long-running show — even though I’ve only done it three years — you don’t want to get into a groove. You don’t want to get into a place where you think, ‘I know how to do this.'”

Between laughs the actor jokes, “Luckily I don’t know how to do it.” Steven Moffat, the current Doctor Who showrunner who took over in 2008 but plans on stepping down after 2017, wholeheartedly disagrees: “Not true.” Of course Capaldi was only being self-deprecating, but the veteran couldn’t help again stressing that “having someone new like Pearl on the show would certainly help and stimulate” his acting chops. And judging by what Mackie told us about her Doctor Who audition, it seems the pair were able to help one another in precisely the same manner.