Millie Gibson On Putting Doctor Who Companion Ruby Sunday at the Center of Her Own Story

Though Doctor Who ostensibly follows the adventures of a two-hearted alien who travels through space and time in a blue police box, the heart of the show is most often found in the stories of the companions alongside him. As a storyteller, showrunner Russell T. Davies has always been particularly fascinated by the emotional journeys of the humans who find their way aboard the TARDIS, the traveling partners who both help the Doctor see the universe through fresh eyes and get the chance to experience its wonders for themselves. Unlike the puzzle box mysteries surrounding the broader identities of companions like Amy Pond (Karen Gillan) or Clara Oswald (Jenna Coleman) during the Steven Moffat era, Davies’s stories are particularly focused on ordinary people who discover that they are capable of extraordinary things. For him, the interior struggles and personal growth of these characters are just as—if not more—important than the truth about any so-called Impossible Girl.

Ruby Sunday (Millie Gibson) was the Fifteenth Doctor’s (Ncuti Gatwa) first companion, a warm and charming young woman searching for her birth mother, whose very ordinariness turned out to be the key to saving the world from the God of Death. Though she departed the TARDIS at the end of last season for a chance to get to know the mom she had never met, the door was certainly left open for her return to a life of traveling through time and space. But, surprisingly, that isn’t the path Doctor Who (or Davies) chooses for her. 

Instead, while Fifteen is busy trying to get his latest companion, Belinda Chandra (Varada Sethu), back to Earth, Ruby gets an Earth-bound adventure of her own. “Lucky Day” is an hour in which the Doctor himself barely appears and never technically interacts with Ruby directly. Yet his influence is still all over this episode, which explores not only how a former companion’s life has changed after traveling with the Doctor, but how their time together has affected the person she’s become for both good and ill. 

“I absolutely loved it,” Gibson, who plays Ruby, tells Paste when asked about returning to the role this season. “It’s always better with the Doctor, but it’s such a privilege to have [an episode] to run by myself. And stepping back into Ruby’s shoes was so nostalgic for me, and it all came very naturally. I feel like she’s more grown up.”

Grown up, however, doesn’t necessarily mean the same thing as okay, and one of the emotional threads running throughout the episode is how much Ruby’s still struggling to readjust to normal life after all her amazing experiences alongside the Doctor. She initially seems lonelier, less trusting, and more guarded than the girl we first met last year. And that’s on purpose. 

“She’s recovering, and you see her learn to deal with that a bit. Pretending everything’s normal,” Gibson says. “She’s trying to figure things out.”

“Lucky Day” sees Ruby become involved with a handsome podcaster named Conrad (Jonah Hauer-King), who has been obsessed with the Doctor since he was eight years old. His fascination with things like aliens, UNIT, and the TARDIS means that it’s easy to see why Ruby might fall for him. After all, he’s not only willing to listen to her stories of traveling through time and space, he—unlike most of her friends, it seems—actually believes what she’s saying. After all, he’s seen the Doctor for himself, something that, in Ruby’s eyes at least, means he feels familiar to her.

“I think in Season 1…her journey has given her a bit of PTSD, so she’s a little more wary about who she lets in now. She was wary about going on Conrad’s podcast. He had to kind of work to bring her walls down,” Gibson says. “But I think it’s really beautiful when you finally see those glimmers of Season 1 Ruby shine through. Even beyond that [flashback], there are moments [with him] where she really seems like her normal self sometimes.” 

The story of “Lucky Day” gives Gibson a chance to play two different versions of Ruby, both her slightly more lost present-day self and a flashback version who is brimming with hope and curiosity, at the very beginning of her journey with the Doctor. And showing that contrast between the two was important to her, as Ruby attempts to navigate both a new relationship and an alien threat. 

“I didn’t know if anyone would really notice the difference [between the two], so I’m so glad you asked about that,” Gibson laughs. “I think I’m a little bit bubblier as Season 1 Ruby, and she’s a little more open. Season 2 Ruby is a bit more grounded. She has her walls up now, and she takes everything in first before reacting.”

Unfortunately, her clear desire to believe the best of Conrad comes with unexpectedly dire consequences. Despite his sweetly awkward demeanor and seemingly nice guy bona fides, his entire schtick was a set-up meant to prove Ruby, her stories, and UNIT as an organization are frauds. What follows is an uncomfortably timely meditation on disinformation, alternative facts, and obsession, as Conrad engages in everything from public doxxing of UNIT employees to armed breaking and entering in the name of finding what he insists is the “real truth”.