Earthshock was the sixth story of season 19 of Doctor Who. It was notable for its high ratings, the deliberately unannounced return of the Cybermen, and the death of Adric.
Indeed, this serial and Time-Flight together offered producer John Nathan-Turner his highest consistent chart positions. Earthshock was the only serial in JNT’s producership whose episodes were all in the top fifty of programs watched on British television.
JNT took a now-well-known publicity gamble with this serial by deciding that he wanted to keep the return of the Cybermen a surprise. Normally, there was a public gallery overlooking the studio floor at Television Center which allowed public viewing of proceedings. For Earthshock, JNT had this area closed and security kept people out. Nathan-Turner also turned down a Radio Times photo shoot to ensure this secret did not leak out.
The death of Adric was also a considerable gamble, since no long-running companion had ever been killed on Doctor Who before. Special, downbeat titles were commissioned for the end of part four, making the final part the only episode, as of November 2013, to have no end theme music.
While there is no doubt that JNT and his team absolutely intended Adric’s unambiguous death, the ending of the story has been materially changed by Big Finish’s The Boy That Time Forgot, during which it was revealed Adric did not die but went on to live in a bubble universe the Fifth Doctor accidentally created, before finally crossing back into the normal universe in Victorian London.
Lieutenant Scott and his team climb up a bleak hillside on Earth, escorting Professor Kyle to a camp set up by Scott’s team. The scanning equipment at the campsite is directed at a cave to detect mammalian life forms. Kyle had been part of a scientific expedition investigating the caves for fossil remains, but the expedition has disappeared. The lack of readings suggests they are all dead. Kyle’s knowledge of the tunnels is necessary to direct Scott and his team into the caves to find out what happened, while two troopers remain outside to maintain a constant scan. As they investigate, the squad is being stalked by two dark figures.
Meanwhile, in the TARDIS, Adric begins arguing with the Fifth Doctor about the lack of attention and respect he receives compared to Tegan or Nyssa. Finally, he declares that he wishes to return to his home planet of Terradon, which the Doctor loudly proclaims is not possible, However, Adric is insistent that he can calculate the coordinates to guide the TARDIS back into E-Space; to the Doctor’s displeasure, Adric begins to write down his calculations.
Scott’s squad splits into two groups, but a strange jangling sound comes over the communications system, and one group ceases contact. Outside, a flare appears on the outside scanner. Walters and Snyder see more life-forms appear on the scanner — the TARDIS crew, which have just landed in the caves. However, Scott instantly assumes that the newcomers must be responsible for the deaths, especially when he is informed that one of the new life signs shows two heartbeats.
While Adric computes his calculations, the Doctor has gone for a walk in the caves. With Tegan and Nyssa, he examines the fossils of dinosaurs on the cave walls. musing that he had always wanted go back and determine exactly how they died. As the wounded party is making slow progress, Snyder goes in to help, but they are attacked by the dark figures. The jamming increases, and Snyder is reduced to a pile of smoking remains. As the survivors start to investigate, they continue to be picked off one by one.
Scott and the remainder of his squad come across the Doctor and his companions and capture them. Scott accuses the Doctor of the murders and, while the Doctor tries to convince him otherwise, the dark figures continue their approach. Digging away at a recent rockfall, they discover the remains of the scientists as well as a metal hatch which begins to emit a trilling sound; Scott orders the Doctor to open the hatch. The dark figures pick up their pace and begin to attack as everyone dives for cover.
The Doctor realizes that the attackers are androids, which is why they did not show up on the scans. The androids appear to be defending the hatch and shrug off the troopers’ counter-attacks. Kyle recognizes the sound the androids are making, and realizes that they were the ones who murdered the others. As an android focuses its gaze on the Doctor, the image is transmitted elsewhere to their masters: a group of silver humanoid robots. Their leader orders that the androids “destroy them at once.”
Inside the TARDIS, a signal is detected. Adric wanders out of the TARDIS, trying to locate the Doctor and determine the source of the signal. He is able to distract one of the androids long enough for Scott and his team to destroy it. The other one is subjected to intense fire att, also resulting in its destruction.
The Doctor has realized that the signal is being transmitted to whatever is inside the hatch. He runs back to the TARDIS and is able to jam the transmission. He and Adric return with the Doctor’s tool kit. Tegan and Nyssa usher the rest back into the TARDIS where they will be safe as the Doctor and Adric open the hatch to discover an explosive device within. The Doctor fiddles around with the bomb and inadvertently reactivates it, but together with Adric disarms it before it detonates. Returning to the TARDIS, the Doctor informs the others that they are going to trace the source of the transmission. The androids’ masters, revealed to be Cybermen, are puzzled as to why the bomb failed to detonate. Reviewing the recorded images transmitted by the androids, they see the TARDIS. They realize the Doctor is involved, and begin to review their past encounters with the Time Lord.
Meanwhile, out in space, a freighter is being inspected by Earth security forces while replenishing its supplies and crew. However, the morale of the crew is low, kept going only because of the promise of their bonus for delivering the cargo on time. Ringway, one of the bridge crew, wonders if the bonus is worth it, with several disappearances having already taken place. Berger seems to think that it is, and suggests Ringway adopt a more cheery attitude towards the crew to maintain their morale and his.
Having arrived on board, the Doctor and Adric explore the freighter, and come across the bodies of two dead security men. Ringway encounters them over the bodies and declares them murderers, the penalty for which is death.
Ringway escorts the two travelers to meet the freighter’s captain, Briggs, a middle-aged woman who is only concerned about the bonus.
Scott and Kyle start to worry about the Doctor and Adric, although only Scott says anything. Scott announces that he wants to go find the Doctor, but Nyssa replies that the Doctor will not thank them for taking such a risk. Scott takes no notice. Tegan, also wishing to help, goes with Scott and his remaining soldiers.
The Cyber-Leader decides that it is time to take control of the freighter, and orders a unit of Cybermen to be activated. The unit marches on the bridge and is spotted on one of the monitors. Briggs orders a blockade set up outside the bridge, despite the Doctor pleading that her men won’t stand a chance if they do that. Sure enough, the Cybermen effortlessly blast through the barricade. At the same time, Ringway turns on the crew and announces that he now works for the Cybermen, having grown tired of Briggs. The Doctor disarms him and closes the bridge doors before the Cybermen can get inside. Briggs seems confident that they can hold out until they get back to Earth, as there are only a few Cybermen; when Adric inquires as to how many cargo containers there are, she realizes that all 15,000 are probably full of Cybermen.
As Scott, Tegan and the others kill one Cyberman and damage a second, the Cyber-Leader has his troops soften one of the bridge doors with a thermal lance. The Doctor taps into the antimatter storage system and uses it to stabilize the door just as a Cyberman breaks through, with the result that the Cyberman is fused into the door. The Cyber-Leader had also fitted explosive charges to the other bridge door, however. Just before it goes to detonate them, the Cyberman that Tegan killed crawls up. His lieutenant points out that all the crew have been accounted for, and the Cyber-Leader erroneously concludes that Ringway lied about the crew numbers.
The explosives are detonated, destroying the bridge door. The Cybermen take the bridge, and the Leader has Ringway killed for his “deception”. The Doctor then sourly jokes, “You never change; always the perfect guest”. The Doctor and the crew members all watch as the additional Cybermen are revived, in order to deal with the other humans. As they march through the hold the Leader declares, “My army awakes, Doctor!”
The Cybermen fit a device to the ship’s computer which locks it on course to collide with Earth. The Cyber-Leader then explains his mission – several galactic powers are going to meet on Earth that day and hold a conference that will unite them in a war against the Cybermen. Their original plan was to use the bomb to virtually destroy Earth, commandeer the freighter and use the army to kill anyone who survived. Due to the Doctor’s interference, the Cyber-Leader has switched to his backup plan – crash the freighter into Earth. As it is powered by antimatter, the resulting blast will be every bit as devastating as the bomb would have been.
Tegan gets separated from Scott and his men and is eventually captured. Scott returns to the TARDIS, but is followed by a pair of Cybermen. The troopers kill the Cybermen and take their guns, but Kyle is killed in the process. Tegan, meanwhile, is taken to the bridge. Noting the Doctor’s reaction when she is brought into the bridge, the Cybermen comments that emotions must be a severe handicap for the Doctor. The Doctor argues that emotions are what makes life worth living – in response, the Cyber-Leader orders that Tegan be killed. The Doctor throws himself in front of Tegan, and the Cyber-Leader remarks that emotions are a disadvantage, as now he only has to threaten to kill Tegan for the Doctor to obey him.
Scott and the troopers leave the TARDIS again, as the Cyber-Leader decides to leave the ship in the TARDIS. Briggs, Berger and Adric are left on-board so that a few remaining Cybermen can observe their reactions, and thus better understand human weaknesses. The Doctor and Cybermen leave in the TARDIS, and Scott takes out the Cybermen guarding the bridge. Briggs wants to abandon ship, but Adric tells her that he might be able to override the device controlling the ship’s computer. He overrides one segment of it and Berger tries to bring the ship out of warp, but this has an unexpected effect – the freighter jumps into a time warp and goes backwards in time. Tegan is relieved at this, believing the Earth to be safe. Her relief is soon shattered when the Doctor points out that it has made the situation far worse – not only will Earth still be destroyed, but with the freighter now back in an earlier point of its history, the planet’s whole existence will be nullified.
Adric overrides another part of the control device, bringing the freighter out of warp – but still perilously close to Earth. Briggs decides that it’s time to abandon ship, but Adric is still determined to break the codes. Scott drags him into the escape pod, only for Adric to jump out at the last second and continue his efforts. Back on the TARDIS, the Doctor points out that they have travelled back 65 million years – at about the time the Earth collided with an object which killed the dinosaurs. Tegan realises that the object was really the freighter, and that rather than erasing Earth’s history, the explosion will form a key part of it.
While Adric continues in his efforts, Scott signals the TARDIS and informs them that Adric’s still on-board. The Cyber-Leader decides to kill the TARDIS crew, but Tegan jumps on him and the Doctor breaks up Adric’s gold-plated Mathematics Achievement badge into the Leader’s chest unit. The maddened and asphyxiating Leader fires its gun aimlessly, damaging the TARDIS console in the process. The Doctor grabs the gun and shoots the Leader, killing it.
Adric is closing in on fully deactivating the control device, but is thwarted when a damaged Cyberman tries to shoot him. The shot misses Adric and destroys the freighter’s controls instead, leaving no chance of altering the freighter’s course. Adric serenely muses that now he will never know if he was right. The Doctor tries to save Adric, while Nyssa quickly deals with the Cyber-Lieutenant. The TARDIS console is too damaged. The Doctor, Nyssa and Tegan watch helplessly as the freighter explodes, killing Adric. As Nyssa and Tegan begin to weep, the Doctor remains silent, shocked at his failure in saving his companion and friend…
The episode ends with silent credits to mark Adric’s death, rolled over an image of his shattered star-shaped badge.