Tom Hiddleston reveals how 'Loki' fixes time travel in the MCU

Time travel shows play by their own rules. However, establishing those rules can be a tricky needle for TV writers to thread. Make them too strict, like the Time-Turner in Harry Potter, and there’s no room to address the plot holes that will inevitably pop up. Too loose, like the “some moments are fixed, some are in flux” approach of Doctor Who, and it all seems arbitrary.

When it comes to Loki, that pressure is even greater. The time travel rules implemented in this Disney+ series won’t just affect its next six episodes but the entirety of pop culture’s biggest franchise. And the man tasked with writing this rulebook? Loki head writer Michael Waldron.

Luckily, it’s hard to imagine anyone better-prepared.

“What are the institutional rules of time travel?”

An experienced hand at visualizing time travel on screen, with Rick and Morty and the best time travel movie never made in his back pocket, Waldron creates a world in Loki that’s centered around order and chaos.

Of course, Loki (played again by Tom Hiddleston) prefers chaos, but the Time Variance Authority he comes into contact with across the series is everything he’s not. This sprawling bureaucracy has dedicated all of its resources to keeping “variants” like Loki at bay. In realistically depicting what would happen once the TVA met its match in the rogue Asgardian, Waldron tells Inverse one question was at the forefront of his mind: “What are the institutional rules of time travel?”

Loki’s initial explanation of the quantum physics that allow characters to leap-frog between timelines isn’t unlike the demonstration we saw in Avengers: Endgame. There’s one timeline — the Sacred Timeline — and anything that branches from it is a dangerous divergence. But for Waldron, applying those rules to a six-hour Disney+ series was a much more difficult task.

“After really defining for ourselves generally what the emotional arc of the series was going to be, we then had to step way back,” he says. “It's not a time travel movie. It's a time travel TV series, which means fans are going to have a week between each episode to scrutinize our logic. So it's got to be as airtight as possible.”

“They have defined themselves as benevolent guardians of a tidy timeline.”

In Loki, we learn the TVA’s job is to intervene within “variants” before they bring the Sacred Timeline too far off the beaten path, potentially creating a multiverse along the way.

For Hiddleston, exploring the TVA and its work was one of the biggest attractions of Loki — aside from starring in his own story after turning up in supporting rules for six previous Marvel movies, of course.

“I find it so exciting and so intriguing,” Hiddleston tells Inverse, “that there might potentially be a bureaucratic organization and institution that has to govern the order of time, and that they are attending to events unfolding according to these predetermined outcomes.”

He adds: “They have defined themselves as benevolent guardians of a tidy timeline. And if ever there’s a branch that they think isn’t quite right, they could prune it.”

Loki’s time travel rulebook

Before the audience, or even Hiddleston, could understand Loki’s conception of the TVA or its treatment of time travel, the series’ writers had to understand both ideas. Easier said than done in a room full of creatives.

“It necessitated a lot of standing at whiteboards, writing, drawing lines with other squiggly lines and yelling at each other,” says Waldron. “At the end of that, we had a good foundational knowledge.”

From that back-and-forth came the “sacred timeline,” as well as the idea of Time Keepers.

“We had to be much more scientific frankly, about it and really, really rack our brains to make sure that this made sense,” Waldron says, discussing Loki’s rules at large. “I'm very proud of the sci-fi concepts in this show.”

But “airtight” logic is difficult to come by with a subject as complex as quantum physics. Whether in theaters or airing on Disney+, titles within the MCU are by design accessible to all, including children. How do you make a topic scientists devote their lives to studying easy to parse for the youngest MCU fans?

Enter Miss Minutes, an adorable bronze clock brought to life by animation voice actor powerhouse Tara Strong. Waldron acknowledged the iconic “Mr. DNA” segment from Jurassic Park as a source of inspiration for the primer on the TVA that Miss Minutes delivers early in the season. The team behind Loki had another crucial tool at their disposal in an audience surrogate.

Characters who are able to ask questions the audience wants to ask, audience surrogates are often essential to demystifying the plot details of a series early on. In this case, Loki fit the bill perfectly.

Like audiences, the God of Mischief hadn’t previously encountered the TVA and has no idea what he’s in for as the series begins, allowing plot information to be teased out gradually for all involved. “We realized less is more, to give just enough,” Waldron says.

“Explain it to me again.”

There’s was another key in communicating the rules of Loki’s world to viewers: the actor himself. Hiddleston has inhabited the role of Loki for a decade now, but Loki’s version of the God of Mischief hails from the MCU’s infancy. In other words, this Loki has major ego issues and a hefty dose of entitlement.

“It was really interesting because I had to sort of unstitch the evolution of things that I remember doing, which is really peculiar,” Hiddleston says. “It was quite a fascinating place to go back to, and also a thrill because it gave us a new anchor for a new journey of discovery and adventure.”

The rules of the TVA and Loki as a whole are only as believable as Hiddleston’s performance makes them feel, and he gives it his all in this series, whether bickering with bureaucrats pushing paperwork or shooting rapid-fire questions to Owen Wilson’s Agent Mobius.

Of course, Hiddleston first had to get his head around those rules himself.

“All I remember is there were lots of different colored pens on a whiteboard, me being confused and saying, ‘Explain it to me again,’” recalls Hiddleston. “But it was fun to dive into,” the actor adds.

Once Hiddleston grasped the series’ overall concept of time travel, allowing him to work that knowledge into his characteristically sly and entertaining performance, what began as a bunch of writers yelling in a room reached its final form: as clear, concise, and impressively effective exposition that not only sets up the series but will lead audiences to contemplate time itself.

“I think the nature of time itself is something malleable,” Hiddleston says. “Even for us as people, time can go fast. Time can slow down a day, can drag out, or it can go by in a flash.”

That malleability is reflected by Loki, where every moment spent in the world of the TVA feels absorbingly real enough that the episode is over before you’ve even thought about checking your watch.

Loki premieres June 9th on Disney+.