Antony Root served as script editor for Four to Doomsday and The Visitation, after which he was replaced by Eric Saward. Saward's work as script editor included the opening serial, Castrovalva, which was filmed later in the production run, and Earthshock, for which Root is credited due to Saward being the scriptwriter. The show moved from its traditional once-weekly Saturday broadcast to twice-weekly, primarily on Monday and Tuesday,[1] although there were regional variations to the schedule.
Black Orchid was the first purely historical story, with no science-fiction elements save for the TARDIS and its crew, since The Highlanders from Season 4; it was also the first two-part serial since The Sontaran Experiment in Season 12, and the first of a regular run of a two-parter every season until the change of format to 45 minute episodes in Season 22.
While the Doctor retreats to the TARDIS Zero Room to recover from his regeneration, the Master kidnaps Adric and sends the TARDIS hurtling back in time to the Big Bang, where it will be torn apart. Tegan and Nyssa manage to save the time machine, and soon find themselves arriving in the town of Castrovalva, a place legendary for its serene atmosphere. There they hope that the Doctor will be able to recuperate from his recent trauma. But the Master is lurking in Castrovalva, and it soon becomes clear that he has drawn the time travellers into a trap from which there may be no escape.
Trying to get Tegan home, the Doctor instead lands the TARDIS on a spaceship heading towards Earth. Its owner, the frog-like Monarch, has visited Earth four times in the past, kidnapping specimens of human culture on each occasion. His true goal, however, is to find a way to travel faster than light, thereby going back to the beginning of time where he hopes to meet God, whom he believes is actually himself. In pursuit of this aim, he has exhausted the resources of his home planet, Urbanka. Now he intends to transplant the Urbankans to Earth – and eradicate humanity to make room for his people.
The TARDIS brings the Doctor, Adric, Nyssa and Tegan to the idyllic jungle world of Deva Loka, which is being surveyed for possible Earth colonisation. Deva Loka is already home to a race of apparent savages, however: a mysterious people with strange powers which have mentally unbalanced the members of the expedition. To make matters worse, an ancient enemy of the natives – a serpentine being called the Mara – still lurks on Deva Loka. The Mara is intent upon revenge, and latches onto Tegan's mind as its bridgehead to victory.
In the 17th century, the Great Plague is rampant throughout England. The Doctor, Adric, Nyssa and Tegan discover that aliens – the Terileptils – are operating in a small village. They have taken control of much of the local population and are driving away the rest using an android disguised as the Grim Reaper. With the help of unemployed thespian Richard Mace, the Doctor learns that the Terileptils intend to rid the Earth of humanity, and have amassed an army of plague-carrying rats to help them finish the deed.
The Doctor, Adric, Nyssa and Tegan find themselves in 1925 England, where through a case of mistaken identity they become involved in a charity cricket match at Cranleigh Halt. There, Nyssa discovers that Charles Cranleigh's fiancee, Ann Talbot, is her exact double. The Cranleighs harbour a dark family secret, however: a hideous monster hidden in a secret wing of their house. Fixated on Ann, it breaks out during a costume ball and attempts to kidnap her... but takes Nyssa by mistake.
In the 26th century, the Doctor, Adric, Nyssa and Tegan come to the aid of a platoon of soldiers investigating the murder of a scientific team in a cave complex on Earth. The Doctor discovers that the killers are actually androids serving the Cybermen, and are guarding a bomb intended to destroy the planet. The Doctor disarms the explosive but by tracing the detonation signal, he learns that the greatest danger is yet to come. The Cybermen have secreted themselves on board a freighter heading for Earth, which will unknowingly serve as the bridgehead for a massive invasion.
When a Concorde disappears, the Doctor discovers that it has been hijacked back through time to the Pleistocene Era. Arriving there, he, Nyssa and Tegan find that the Concorde's crew and passengers have been enslaved by the sinister Kalid, who is forcing them to excavate a sanctum within a mysterious citadel. Entombed within is the consciousness of a gestalt race called the Xeraphin, who possess devastating mental powers. The Doctor learns that Kalid is really the Master, who plans to harness the evil side of the Xeraphin in order to wreak havoc throughout the cosmos.
Broadcast
The entire season was broadcast from 4 January to 30 March 1982. For the first time in the series' history, episodes were not broadcast on Saturdays, but in a twice weekly format on Mondays and Tuesdays.
