Why is Doctor Who series 12 so Earthbound?

Spyfall, episodes one and two? Earth. Orphan 55? While presented as an alien planet, that was Earth too. Nikola Tesla’s Night of Terror was Earth, as was Fugitive of the Judoon, as was Praxeus, as are the next two upcoming episodes (as far as we know).

And out of these eight episodes, five will have been primarily set on present-day Earth, albeit in different locations. Frankly, we’re beginning to wonder if the TARDIS has been secretly clamped.

So why is the Doctor so attached to Earth this series? Well, there’s a few possibilities. Some fans have wondered whether this anomaly (combined with recurring themes like DNA being rewritten and surprise teleports) hints towards a larger theme of the series, with a specific reason being planned for why the TARDIS is so set on returning to the same place.

Maybe the Doctor has been exiled again like her Third incarnation, without even realising? Maybe the TARDIS keeps pulling her back there to try and get her attention to some grave new threat arising on present-day Earth? Is it a pull between the Master’s abandoned TARDIS and the Doctor’s own? Or maybe this in some way links to Jo Martin’s mysterious new incarnation of the Doctor – is the TARDIS trying to give the Doctor a clue that the answers are on Earth?

Well, it’s all possible – but it could also be a coincidence. Because despite appearances, modern Doctor Who doesn’t actually spend that long visiting alien planets.

The first revived series in 2005 flitted between Earth and one specific space station – Satellite Five – while series two managed two largely space station-set stories (The Impossible Planet/The Satan Pit and The Girl in the Fireplace) and a planet so like Earth it was actually called New Earth.

Series three went back to New Earth, another spaceship staffed by humans (again, not a planet) and the dead planet Malcassairo. And it wasn’t until 2008’s series four that visiting alien planets became more of a norm in episodes like Planet of the Ood, Midnight, The Doctor’s Daughter and Silence in the Library/Forest of the Dead.

During Matt Smith’s entire Doctor Who tenure of 44 episodes, just 13 were set primarily away from Earth, and most of those were space station or spaceship-set. 12th Doctor Peter Capaldi had a similar ratio in his 40 episodes, leaving Earth behind as a main setting for 15 episodes.

In other words, it’s not unusual for Doctor Who to prioritise Earth as a setting. And who can blame them for spending a lot of time there? Earth is where the Doctor’s companions are always from, after all, and in real life it’s the planet upon which the series is conceived and filmed.

It wouldn’t be practical to create a fully-imagined complex alien society every other week, and audiences might struggle to relate to it as easily as Earth-based stories. By contrast Earth comes pre-made and pre-explained, because, well, we all did the background reading by living here all our lives.

There’s a reason the Doctor never seems to visit the past of alien civilisations, after all – it’s just not that interesting for the real, human people living at home, even if technically there’s no logical reason for why she’d be so keen on human history compared to every other species in the galaxy.

So yes, there's a logical explanation for everything. But forget the bigger picture - because the fans also aren't wrong to have noted this unusually long period on terra firma.

While in 2018 Whittaker's Doctor did manage to get off-world for four out of 10 stories (which is about the same as or only just under the average rate per Doctor), this year is a bit of an anomaly. Even without knowing details of the double-episode finale, after eight episodes on Earth (nine if you count 2019 special Resolution) the 13th Doctor will inevitably have visited fewer worlds and travelled into space less in 10 episodes than almost any Doctor in a similar period bar Christopher Eccleston's Ninth Doctor.

Going forward, it'll be interesting to see if that changes. For now, though, as an unbroken run of Earth-based episodes this year’s series will definitely take some beating. Here’s hoping the mysterious two-part finale takes us somewhere new and unexpected…

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