Ten weeks after giving birth to her son, Rose Leslie began filming The Time Traveler’s Wife.

“On the weekend, my husband would have to take some downtime, and then I would step into the role of parenting, which I obviously love,” Leslie tells Inverse. “I felt like I was missing out on my boy growing up.”

Premiering on May 15, the new HBO drama chronicles the highs and lows of an extraordinary marriage between artist Clare (Leslie) and her time-traveling husband Henry (Theo James). While Leslie is in a famous marriage of her own with her Game of Thrones’ co-star Kit Harington, the experience of filming The Time Traveler’s Wife will always be tied to the birth of her child.

Leslie isn’t the only collaborator to experience such a strong connection to this project from creator Steven Moffat. Everyone from her co-star Theo James to series director David Nutter found something personal and powerful in the process of creating The Time Traveler’s Wife. The result is arguably the most intimate time-travel story ever told. Here’s how it all came together.

THE RULES OF TIME TRAVEL is an Inverse special issue exploring the evolution of science fiction’s most imaginative sub-genre. From Marty McFly to Avengers: Endgame.

A Complicated Love Story

Before there was the HBO series (and the 2009 movie), there was Audrey Niffenegger’s best-selling novel. The book introduces Clare and her husband Henry, a man with an uncontrollable ability to travel through time to different points in his life — and his wife’s, too. Clare first meets Henry when she is a child. Henry is her “imaginary” friend until she learns the truth of who he is (or who he’ll eventually be) when she is older.

Like the novel, the series switches from past to present following the evolution of their relationship, interspersing moments from Henry’s time-traveling history and Clare’s childhood memories. We see Henry and Clare at mismatched ages throughout their lives. Sometimes it’s an older Clare, speaking to the audience mockumentary-style about the meaning of love. Other times it’s Henry playing board games with a young Clare — or even Henry meeting up with his younger self.

For Theo James, who plays Henry, this posed an acting challenge unlike any other.

“The younger Henry, he’s more chippy, he’s more chesty, but he’s kind of further down in his gait, slumping in his seat because he doesn’t connect with eye contact,” James says. “He doesn’t have that confidence that an older man does. The older Henry’s more upright. He listens more. He takes longer to answer questions, those kinds of things.”

“For Clare, Henry is the truest, most honest figure in her life.”

Since Clare grew up knowing the older version of Henry, her initial impression of him is as a mentor, not a partner. Clearly, this is already quite complicated, but one of the main criticisms against Niffenegger’s book is the relationship between adult Henry and child Clare. Creator Steven Moffat insists there’s nothing problematic about it.

“There is no sexual element to Henry and the little Clare,” Moffat says. “I don’t think he quite thinks of her as the same person as the one he’s married to because a child isn’t the same as an adult. He just thinks she’s somebody else.”

Rose Leslie doesn’t play all the younger versions of Clare, but this dynamic is something she had to take into consideration as she crafted her take on her character.

“Because he’s always had that pivotal role in her life as a figure of hope and love and because he’s never abused that trust, we obviously had to be very sensitive for it never to venture into grooming,” she says. “For Clare, Henry is the truest, most honest figure in her life.”

Out of Sequence

Because of all these sensitivities, Moffat had to take great pains to assert the time travel “rules” of the show’s universe.

Unlike his previous time-travel project Doctor Who, The Time Traveler’s Wife takes an entirely different approach to time travel. Doctor Who uses an arbitrary combination of “fixed” and “flux” moments in time. (Some moments can be changed, other moments can’t, and The Doctor somehow knows the difference between the two.)

For this show, Moffat went straight to the source material.

“There’s a very neat trick Audrey does,” Moffat says, referring to the original novel. “She explains the entire format of her book, how time travel is going to work, in about the first three pages. People say show, don’t tell. You know what? Sometimes, just tell.”

“It exacts a huge physical and mental toll on him.”

From the get-go, we see the rules of Henry’s time travel.

• He can’t control it.
• Nothing comes with him when he time travels, so he shows up everywhere naked.
• And the timeline in The Time Traveler’s Wife is “locked.”

In the show’s first episode, Henry also explains that his time traveling is a disability, not a superpower. Theo James doesn’t exactly agree with the disability part, but it’s clear to him that Henry’s no superhero.

“For Henry, it’s something that he has to survive,” James says. “It’s dangerous. It exacts a huge physical and mental toll on him.”

We see this in the way James portrays Henry. Before each time he travels, he coughs. We can see the panic and terror on his face. When he arrives at his destination, he has no clothes and immediately gets sick.

And that’s just the physical toll. It’s Henry’s emotional journey that serves as one of the cruxes of the series.

A Labor of Love

Pivotal, life-changing moments in Henry and Clare’s lives are like magnets, pulling the time traveler back to relive them again and again. One of the darkest but most formative scenes in The Time Traveler’s Wife is the death of Henry’s mother, Annette (Kate Siegel).

In the third episode, Henry finds himself returning repeatedly to the scene of his mother’s death. As Annette gets decapitated in a car accident on a snowy winter day, the camera pans to reveal multiple Henrys at all different ages watching the scene in horror.

“The sad part for me is her inevitable doom,” James says. “There’s a bit when Kate’s character zips up young Henry’s jacket and that’s just before she’s about to get in the car and then eventually dies. The idea of a young child who knows that his mother’s going to die and tries to do everything to stop there but can’t is just so sad.”

This moment was also very personal to the show’s director David Nutter, who lost his father in a car accident at the age of one and a half.

“I needed to do something special,” Nutter tells Inverse about his decision to join The Time Traveler’s Wife after a short directing hiatus. “I’ve had a tumultuous last few years of my life.”

“I became a better director because of it.”

Executive producer Sue Vertue says that when HBO suggested they work with Nutter, it seemed impossible given his status as a celebrated Game of Thrones director.

“He was initially only going to do the pilot,” Vertue says, “but we gradually cajoled him in bit by bit until eventually, he said Okay, I’ll do all of them.”

After directing several pivotal Game of Thrones episodes, Nutter suffered a back injury that left him unable to work on Seasons 6 and 7, but he made an illustrious return for the fantasy series’ final season. Then, his life took another turn. He lost his wife to cancer in 2019 and is now coping with a Parkinson’s diagnosis.

“It poses no issue with my directing,” Nutter says. “It doesn’t bother that at all.”

In fact, it gave him a new challenge, one that he was more than up for. “It was really an opportunity to go out there and prove to myself that I could do it. I became a better director because of it.”

Nutter directs all six episodes of the series, which Rose Leslie says helped build and sustain a level of continuity needed to juggle all the back and forth of time travel.

“We didn’t shoot chronologically,” she says. “Having David Nutter there at the helm was a real anchor point for all of us to navigate the shifts that were happening in our head. ‘Cause, there were days when I would play different ages. And so, David provided continuity, and being the fantastic director that he is, there was a lot of support coming from him.”

The Time Traveler’s Wife could be considered a labor of love, but it doesn’t look like labor at all. Thanks to the leading duo of Steven Moffat and Sue Vertue, the cast has assembled into a supergroup of passionate actors and crew members. Together, they created a show that marries Moffat’s signature wit with some truly dark time-travel implications, allowing Nutter and the cast to stretch every muscle they have.

“Working with Steven had a feeling of coming home, of being welcomed into a storytelling family that I’ve been trying to get to for a while,” Kate Siegel says.

Leslie sums it up quite nicely.

“It was magical,” she says. “This is a very incredibly heart-rendering touching tale, and it’s exciting for HBO to explore a love story in this way. There’s a lot of love in Time Traveler’s Wife.”

The Time Traveler’s Wife premieres May 15 on HBO.