The History Behind the Sea Devils, the Earthly Inheritors of ‘Doctor Who’

Doctor Who has plenty of iconic monster designs—even if many of them still largely exist in the shadows of its two most iconic, the Daleks and the Cybermen. But one stalwart has slinked around in the shadows of the sea, even behind those lower tiers of recognizable foes… and later this year they might finally try stepping into the spotlight for good.

That is, of course, the Sea Devils—created in 1972 and now set to be the main antagonistic force of The War Between the Land and the Sea, the spinoff show that will cap off the end of the BBC’s tumultuous partnership with Disney for Doctor Who. They’re a species that has largely endured by an iconic design, and Doctor Who has tried multiple times to bring the Sea Devils back, to varying levels of success over the past half-century, but War Between is both their most high-profile and arguably riskiest attempt yet. As we prepare for the seas to part ways once more, let’s take a look back at their perpetual history of existing in the shadows.

The Rise of the Sea Devils

The Sea Devils were made to exist in the shadow of another Doctor Who race from the moment they first existed. Created in 1972 for Malcolm Hulke’s eponymous serial, the Sea Devils themselves were a follow-up to one of Hulke’s own earlier ideas: the Silurians, introduced two years prior in “Doctor Who and the Silurians.†Both stories played with the premise of re-introducing more alien-esque monsters into the era of Jon Pertwee’s third Doctor, at a time the character was exiled on contemporary Earth and unable to use the TARDIS to travel in time and space (outside of a temporary reprieve in 1971’s “Colony in Space,†the Time Lords wouldn’t permanently lift the Doctor’s exile until 1973’s “The Three Doctorsâ€).

Just as had been the case with the introduction of the Silurians two years prior, the Sea Devils were framed as an ancient species native to Earth that was a precursor to the evolution of humankind. After they were raised from their long slumber beneath the oceans (as a contrast to the Silurians, who simply lived deep beneath the Earth) by the nefarious whims of the Master, the Doctor recognized an opportunity with the Sea Devils that he’d failed to enact with the Silurians: an attempt to broker peace between humanity and another native species of Earth. The second time was not to be the charm, however, with the Doctor forced to destroy the Sea Devils’ operational base when they prepared to take the planet by force.

The Warriors of the Deep

Although “The Sea Devils†made a connection between the titular beings and the Silurians before them, it would take another 12 years for either species to make a return and actually build on that relationship. And even then, 1984’s “Warriors of the Deep†didn’t really start from a point of desire to actually explore the symbiotic link between the Silurians and the Sea Devils but as part of a broader desire behind the scenes to feature more familiar Doctor Who monsters during the show’s 20th anniversary celebrations.

However, the grand return of the Silurians and Sea Devils did not go as planned. Production issues at the BBC brought about by the sudden announcement of a general election by then Prime Minister Margaret Thatcher in the summer of 1983 caused “Warriors†to lose two of its planned filming weeks, leading to a rushed and haphazard shooting schedule. Evidence of the serials’ behind-the-scenes issues is clear all over the final product, from bizarre directorial choices to the costuming for the particularly infamous sea creature called the Myrka, a monster utilized by the Silurians alongside the Sea Devils as a foot soldier that can be seen leaving streaks of still-wet paint along the set due to barely being completed before filming.

The lackluster reception to the story—even with its timely parallels to the Cold War, with the Silurians and Sea Devils attempting to instigate mutually assured destruction between humans so they could once again reclaim Earth’s surface for themselves—meant that neither species would return before Doctor Who‘s cancellation five years later in 1985.

The Silurians Return

It would take another 26 years—and five years after Doctor Who‘s own revival in 2005—for Doctor Who‘s monster odd couple to make a comeback, but even that treated the Sea Devils as an afterthought. 2010’s “The Hungry Earth/Cold Blood,†penned by future showrunner Chris Chibnall, revived the Silurians in a radically overhauled fashion, framing the creatures in its story as coming from a different evolutionary branch of the Silurian race in comparison to their prior appearances, allowing the series to completely update their design.

The modern Silurians were green-scaled reptilians, lacking the third eye seen on previous Silurians, and instead featured much more humanoid features, intended to allow performers to better display emotions. But perhaps most crucially, the previously established connection between the Silurians and the Sea Devils went unmentioned, with the latter not appearing at all. Although the redesigned Silurians would make more minor appearances after their 2010 return (mostly through the character of Madame Vastra, a Victorian-era investigator who became an irregular supporting character throughout the tenure of showrunner Steven Moffat), they have yet to receive a second major story since Doctor Who‘s revival.

The Sea Devils themselves took another 12 years—38 since their last on-screen appearance—to make a comeback in the 2022 special “Legend of the Sea Devils.†Once again separated from the Silurians, as written by then-showrunner Chris Chibnall, “Legend†stands in stark contrast to the approach taken with the Silurians previously; the Sea Devils of this story remained aesthetically faithful to their prior appearances, although the episode itself was poorly received beyond that fact. But with Doctor Who on the cusp of handing over to another era, the species’ comeback was short-lived.

The War Between

The wait for the Sea Devils to get another chance wouldn’t take as long as the past gaps in their TV history, but it would continue a similar trend of other events largely overshadowing them. In a surprise announcement at the 2024 San Diego Comic-Con, it was confirmed that the Sea Devils would be the focus of the first Doctor Who spinoff show produced during the series’ new partnership with Disney, The War Between the Land and the Sea.

The tale is much the same as the Sea Devil’s past adventures—the ancient race rising from the oceans to tussle with modern humanity over inheritance of the Earth. And like the Silurians before them, the Sea Devils have now been largely redesigned, with some sporting faces more traditionally inspired by their old appearances and some gaining more humanoid features. They’ve also finally been given a new name, Homo Aqua, to acknowledge after 53 years that “Sea Devil†was a name given to them by a shocked human in their first story, rather than their actual species.

But again, the return of the Sea Devils has fallen out of the spotlight in the face of external events. In late October, it was confirmed after months of speculation that Doctor Who and Disney’s partnership had spectacularly disintegrated after just two years, with both the BBC and the House of Mouse going separate ways… and leaving The War Between out in the cold. The new series, the last episodes included in Disney’s prior deal, will now air in the UK this December, while their release on Disney+ internationally is still set for an unknown point in 2026.

How long it will take the Sea Devils to return after being the subject of a high-profile behind-the-scenes breakup remains to be seen… but going by their history, Homo Aqua has always had to roll with the punches of never quite managing to get out of murky waters when it comes to their place in the Doctor Who monster canon.

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