Doctor Who, the longest-running science fiction series, is about to embark on a fresh journey with its latest season featuring Ncuti Gatwa as the 15th Doctor. The recently dropped trailer for the upcoming season shows the Doctor and new companion Ruby, portrayed by Millie Gibson, traveling through various periods in history, from the modern age to the prehistoric times when the Earth was dominated by dinosaurs. More importantly, the trailer also drops a very pointed Ray Bradbury reference, hinting toward the exploration of the timeless concept of the butterfly effect in time travel.
In fact, this might be the first time in Doctor Who history that we receive a proper explanation of the butterfly effect concept and its relationship with time travel in the series and not just the usual “timey wimey” explanation we’ve been getting for the past 17 years. But before we dive further into this discussion, let’s dissect the important part of the trailer. Namely, the TARDIS lands in Wyoming, North America. But instead of landing near the Buffalo Bill Center of the West (a famous Wyoming location), the iconic police box lands amidst the flora and fauna of the Mesozoic era.
As she’s leaving the TARDIS, Ruby asks the Doctor if she would change history by stepping on a butterfly, to which the Doctor responds, “That’s not going to happen, is it?” That’s a valid answer because time in the Doctor Who universe is much tougher and less malleable than when it first appeared in the series, and it could take a lot of hammering for things to get proverbially out of whack. But Ruby, with all the luck that Murphy’s Law can muster, then steps on a butterfly, which then sends ripples throughout time because the whiplash turns Ruby into a reptilian humanoid (similar to Silurians from the show) as a result.
So, how did Ruby turn into a reptilian humanoid if time is not so easily broken or tampered with? Well, just like the events of “The Long Game” in Episode 7 of the first series of Doctor Who’s revival clearly demonstrated, the rules of time can be rewritten. In the follow-up episode entitled “Bad Wolf,” the Doctor overthrew the manipulative regime that held humanity in its clutches in the year 200,000. However, upon his return in 200,100, he discovered that the station had been repurposed and media control over humanity had not subsided. This demonstrates continuity in time travel within the Doctor Who universe.
However, it’s also worth noting that in the 1967 “Enemy of the World” episode, Salamander (the antagonist) is still a looming presence in 2018, but he’s then nowhere to be found in “The Women Who Fell to Earth,” which is set in the same year. As a result, we can conclude that time exhibits both qualities; it’s both malleable and fixed, depending on the particular story needs of the Doctor Who episode at the time. The show’s long history and time-traveling premise allow for a broad interpretation of what might be considered canonical within its universe, and the same applies to time and its laws.
The truth is that Doctor Who never really went all-in on the butterfly effect, where an action in the past would create a completely different future. Instead, we’re given several “fixed” points in time that stand unchangeable, while the rest of time swirls and fluctuates around them. This made the butterfly effect only a real convention when it suited the writers and the narrative. For example, the Doctor was unable to change the events of the volcano eruption in “The Fires of Pompei,” but his presence there made him and Dona an actual part of history.
But then, in “Thin Ice,” Bill Potts wonders whether she would change the future by stepping on a butterfly, only for the then Doctor to joke about that same thing happening to Bill’s friend Pete, who stepped on a butterfly and has erased himself from the existence. That is, quite conveniently, the only reference of Bill’s friend Pete in the show. It’s quite obvious that the show played fast and loose with the butterfly effect and how it affected the cascading changes in the show’s timeline. However, the new show might actually change that.
The newly dropped Doctor Who trailer suggests that the series seems to be re-evaluating its position on the domino effect in history that a stapled reference to the butterfly effect implies (similar to what they did with Mavity), perhaps with the intention of making those effects more prominent in the upcoming episodes. Given the fast and loose use of the butterfly effect in the previous episodes and seasons, we’re prompted to ask: Has Ruby stepped on a different kind of butterfly? And if yes, what makes this butterfly so special that it potentially changes the entire future of our planet?
While we can’t say for sure, it would seem that the butterfly effect takes a more central place on the Whoniversal stage, especially since we see the Doctor and Ruby appearing in various timelines in Earth’s history that have been significantly altered. This suggests that the series might explore the butterfly effect by using it as a key narrative driver for the entire season.