This week finds us visiting the small village of Devesham in this four-part story penned by Terry Nation, which aired from 22 November to 13 December, 1875.
The Doctor (Baker) and Sarah-Jane (Elisabeth Sladen) arrive back in the right time, 1980, but still not quite to London. Instead they discover the little town of Devesham, which seems to be completely deserted, the phones don’t seem to work, and when people do show up… they are strange figures all in white with helmeted heads, quickly followed by some oddly behaving villagers.
The Doctor and Sarah suspect there may be something afoot because of the nearby Space Defense Station, which is overseen by UNIT. Upon investigation, the Doctor learns that the station is being run by Guy Crayford (Milton Johns), and seems to be taken over by the same strange thing that happened to the villagers… They’ve been replaced with androids, including Harry (Ian Marter) and their old friend Benton (John Levene), crafted by an alien species known as the Kraals, who have plans of taking over the Earth.
The TARDIS mysteriously vanishes, leading the Doctor to suspect that perhaps they aren’t really on Earth. The pair become suspicious of Crayford… Sarah doesn’t believe they could have encountered the man, because he was believed to have died on a space mission.
When the Doctor is captured, Sarah-Jane sneaks in to help him escape, but as they make their run for freedom, Sarah gets grabbed, and the Kraals use the opportunity to replace her with an android. The Doctor rumbles her very quickly, and finally reveals to the real Sarah that they aren’t on Earth, and explains that is where the TARDIS has continued on to, completing it’s journey as programmed.
As the Doctor and Sarah escape the fake Earth, they learn that the Kraals are using the facsimile as a testing ground for their conquest of Earth. But, the Doctor gets captured (again), and this time the Kraals copy the Doctor’s patterns into an android.
When they finally reach Earth, and welcome the help of both Benton and Harry to help stave off the invasion before it can get underway. But their android doubles have arrived as well, and the pairs will have to face off against one another one last time, before the end of the tale.
Happily, the Doctor and Sarah-Jane work to resolve everything as best they can, stopping the Kraals and deactivating all the androids, including their robotic doppelgänger, just in the nick of time.
Sarah-Jane almost elects to leave the TARDIS, hinting at an upcoming departure no doubt, but the Doctor promises to take her back to London safely… though by the title of the next story, I wouldn’t be so sure about them arriving in London just yet.
Next time, they encounter The Brain of Morbius!