Before stepping aboard the TARDIS, new Doctor Who companion Millie Gibson got some helpful advice from a Who alum.

The 19-year-old actress stars as Ruby Sunday on the hit sci-fi series, traveling through space and time with Ncuti Gatwa’s Fifteenth Doctor. Gibson made her debut in the 2023 Christmas special, “The Church on Ruby Road,” and up next, she and Gatwa will headline their first full season of Who (premiering May 10 on Disney+ and the BBC).

In an interview for Entertainment Weekly’s recent Doctor Who cover story, Gibson revealed that she’s long been a fan of the show, and she grew up bingeing episodes of Matt Smith’s era with her dad. So, when she found out that she would be joining the series herself, she reached out via Instagram to one of her favorite past companions: Karen Gillan, who played Amy Pond from 2010 to 2012.

“I just expressed my love and admiration, and I did get a reply from her!” Gibson says. “She was like, ‘I’m so sorry! I’ve just figured out my Instagram DMs!’ But she was really lovely, and she gave me such down-to-earth wise words. It’s such a unique role, so your experience is very much like no other. So, when you get to talk to a past companion, it’s very reassuring and beautiful to be told that it’ll be okay and to enjoy the ride.”

James Pardon/Bad Wolf/BBC Studios

Gibson launched her career working on the iconic British soap series Coronation Street, before departing in 2022. On her very last day filming that show, she got a call from her agent, who revealed that returning Doctor Who showrunner Russell T Davies was a fan and had invited her to audition to play the new Who companion.

“I was kind of thinking, ‘God, that will be a laugh,’” she says now, shaking her head. “It’ll be a nice little memory for my first audition after Corrie, and I’ll never hear of it again. And that was the start of a long journey, and it’s been a whirlwind ever since.”

As revealed in the Christmas special, Ruby was born on Christmas Eve in 2004, and her birth mother left her abandoned on a church doorstep. She was soon adopted by foster mother Carla Sunday (Michelle Greenidge), and after a chance meeting with the Doctor, they set off together in the TARDIS.

“There’s never been a younger sort of relationship, where it’s more like two girls in school, giggling and gossiping,” Gibson teases. “Me and Ncuti have a similar relationship to the Doctor and Ruby, which really helps. It’s just constant laughter and platonic best friends.”

Natalie Seery/Bad Wolf/BBC Studios

“If we were at school together, we would be such trouble,” Gatwa adds. “The teachers would never allow us to sit together. We’re curious and we’d be looking for an adventure somewhere in the room. And I was like: That is the vibe I want for the Doctor.”

Despite previous press reports that Gibson would be leaving after this season’s end, she and Davies confirm that Gibson — and Ruby — will play a major role across this season and the next. (Andor actress Varada Sethu is also confirmed to join Gibson and Gatwa in the TARDIS in season 2.)

“Russell’s given me the gift of a really beautiful story arc, not only in season 1 but in season 2 also,” Gibson adds. “Her family definitely structures her beliefs and her positivity. I think because I’m playing my age as well, it was so easy to express that sort of giddiness and young energy that Doctor Who’s not seen before.”In the meantime, she says, she can’t wait for Who fans to fall in love with Ruby, just as she fell in love with Amy Pond all those years ago.

“The thought of me being some little girl or little boy’s companion is a really special thing,” she says with a smile. “Because that was me when I was younger.”

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