In a human extraterrestrial colony a band is happily practicing while a few officials oversee them. The preparations are interrupted by a panicked man named Medok, who is trying to escape the colony. Hiding from the colony’s guards on the planet’s (of course) rocky landscape, Medok notices the TARDIS materialize and attacks the Doctor and the others when they emerge, ranting about the beings who have taken over. The guards, led by the security chief Ola, capture Medok, calling him “one of their last patients.” Ola offers to introduce the Doctor and the others to “the Pilot” of the colony, who will give them thanks personally for helping capture Medok. When Jamie asks where they are, the Doctor says they’re in the future on a planet much like Earth, but admits that he’s “only guessing.”
At the Pilot’s headquarters, the Doctor notices that music is constantly played throughout the colony and the Pilot explains it’s how the day is regulated at the colony. The Pilot leads the visitors to the Refreshment Department, which offers a wealth of spa activities. While the TARDIS crew enjoy themselves, Medok is interrogated and insists that he’s seen strange beings all over the colony. Concerned about Medok, the Doctor leaves the others to check on him just as he’s being imprisoned. The Doctor sneaks into Medok’s cell and asks Medok if the things he sees crawl on the ground. Medok is shocked at the Doctor’s question, but still pushes the Doctor aside and flees from his cell. Ola wants to arrest the Doctor and send him into “the Pits” for hard labor, but the Pilot stops him. However, the Pilot becomes hostile when the Doctor mentions Medok’s comment about things crawling on the ground, and warns that comments like that could get a person in the hospital for correction. Ben notices monitors across the colony broadcast a message from a man titled the Controller, who tells the people to “return to their work and play with fresh heart and renewed energy.” Ben asks one of the colonists if the Controller is a politician. The colonist replies that the Controller brings the people encouragement. Ben quips, “He’s not a politician then!” The Doctor asks the colonist what exactly the other colonists who are busy at various consoles do, and the colonist explains that they channel refined gas, but doesn’t say why.
Later the Doctor finds Medok and finally gets Medok to trust him a little. Reluctantly Medok explains that the creatures, whom he calls Macra, he sees move at night and look like giant insects with claws. Other people in the colony have seen the creatures, but claiming to have done so earns people a one-way trip to the hospital. The Doctor leaves Medok to hide in a construction site and learns that the colony has a strict night curfew when Ola escorts him and his companions to their sleeping quarters, but of course the Doctor takes advantage of the fact that all the guards are looking for Medok in order to sneak away to explore the colony at night. The Doctor rejoins Medok and while hiding from Ola and a patrol of guards they’re approached by a Macra in the flesh. In an excited outburst, Medok reveals himself to Ola and says that the Doctor can finally confirm that they spotted the monster. However, Ola is nonplussed and sends the Doctor to be tried by the Pilot. Before the Doctor can try to verify Medok’s story, Medok makes a statement to Ola that the Doctor was trying to get him to surrender to the authorities, which the Doctor reluctantly agrees with. After the Doctor leaves, the image of the Controller comes on and orders that the Doctor and the visitors “be turned” since there “cannot be criticism of the colony.” The Pilot orders that the Doctor and the others be exposed to subliminal messages in their sleep. Besides the Doctor, only Jamie resists the subliminal programming and, when he tries to wake up Ben, finds that Ben is already looking forward to working for the colony. Meanwhile the Doctor wakes up Polly and tries to deprogram her, urging, “Don’t do anything of the sort! Don’t just be obedient! Always make up your mind!” Unfortunately, even though the Doctor destroys some of the equipment, it’s too late to save Ben from being brainwashed, and he turns the others in to the authorities.
The Doctor is sent to the Pilot, while at the hospital Medok has been deemed a helpless case and is going to be sent to the Pits. Ben and Polly fight at the construction site where the Macra appear. Ben can only repeat like a mantra, “There is nothing harmful or evil in this colony,” while Polly is grabbed by a Macra. Ben momentarily snaps out of their brainwashing and helps Polly, only to find they’re being pursued by the Macra. At the Pilot’s office, the Doctor not only pleads guilty to destroying the brainwashing equipment, but admits, “I’m proud of it!” Ben and Polly are taken to the Pilot’s office too, where Polly insists on their attack by the Macra, but Ben, whose brainwashing has kicked back in, insists that there were no such beings. The Doctor theorizes that the Pilot and all the colony’s leaders have also been brainwashed all their lives. Jamie raises the possibility that the Controller is just a face on a monitor and the Pilot pleads with the Controller to prove that he’s an actual person. Suddenly a nervous old man in a uniform appears on the monitor. An outside voice commands him to restore order, but the old man just bursts into tears and is attacked by a claw. Despite the extremely blatant evidence, the Pilot barks that the Doctor and the companions be taken to the Pits. The old image of the Controller returns and confirms the Pilot’s orders regarding “the strangers.”
As a song with the cheerfully sung lyrics, “We are all happy to work!” plays, the Doctor, Polly, and Jamie are rejoined by Medok, who explains that they’ll have to do work in the mines exposed to gas that will sooner or later kill them, even though no one knows what the gas is used for. Given that his captors think he’s old (which is the only part of the situation that even annoys the Doctor), he’s forced to be a supervisor, spied on by a still brainwashed Ben. When one of the supervisors is accidentally knocked unconscious by a gas leak, Jamie manages to steal his keys and uses them to get into a suspicious and seemingly abandoned yet heavily locked shaft, followed by Medok and triggering the mine’s alarms. The Controller forbids the mine’s officials to send guards into the shaft. In the shaft, Jamie finds that something has killed Medok; that something, the Macra, is not far away either. The Controller orders that the gas be poured into the shaft, but the Doctor realizes that there must be a motive other than trying to kill Jamie and deduces that the Macra need the gas to keep themselves alive. Back in the mine’s control room, the Doctor pretends to help by meddling with different valves and gets information on what he needs to do from the supervisor’s pleas to stop interfering, saving Jamie and stunning the Macra threatening him by blasting oxygen into the shift. Then the Doctor pickpockets the supervisor’s keys, locks him outside the control room, and he and Polly flee into a corridor filled with pipes. Jamie escapes the shaft through a grate and ends up pretending to be a dancer practicing with a trope of the Happy Colony Finals, but is soon caught. The Doctor and Polly hear the Controller’s voice and follow it to a room where a Macra is operating a control panel.
While the Pilot and Ola argue over the fact of Jamie’s escape, the Doctor casually strolls in and asks why they are fighting in a happy colony. While Polly tries to convince the Pilot, the increasingly shrill Controller demands that the strangers be rounded up and that all the colony’s leaders return to work. The Pilot is persuaded enough to risk disobeying the Controller. The Pilot frets over disobeying the law, but the Doctor points out, “Bad laws are meant to be broken” and leads the Pilot to the control room with the Macra, which finally breaks the last vestiges of control over the Pilot. Under the Controller’s orders, Ola traps the Doctor, Polly, Jamie, and the Pilot in the pipe corridor, which is quickly filled with gas. Ben, who has finally shaken off the Macra’s programming, follows the Doctor’s instructions and manipulates the mine’s controls to blow up the part of the mine where the Macra live. In the middle of the Happy Colony Finals, the Pilot appears and rededicates the celebration in the Doctor’s honor.
More a production note, but this is the first time that the title screen changes. The basic psychedelic patterns in the intro remain the same, but now the logo of the “Doctor Who” font has changed and is overlaid with Patrick Troughton’s face, setting a pattern of using the actor currently portraying the Doctor’s face that will last for the rest of the classic series.
So this is what happens when you cross ’60s Doctor Who with “1984” with a dash of They Live. Despite having a really rushed conclusion that threatens to slam the story’s momentum against the brick wall, this is definitely a classic episode – which makes it a shame that only a few scattered minutes of footage survive of the entire serial. Even if you just watch a fan reconstruction or listen to the BBC’s official audio release, it’s worth it. Even without 99% of the visuals, the Doctor still comes across as a cheer-worthy anti-authoritarian champion and the construction of the colony’s society is conveyed as genuinely unsetling (especially when the old man is “revealed” as the fake Controller). The social commentary might be as on the nose as a fist to the face, but having a protagonist who explicitly urges people to break laws they think are immoral and to always question orders really isn’t as common as you might think. Plus when you think about it a premise all about giant parasites who brainwash people into mindlessly working all the time for the sake of nothing but the parasites’ own survival in exchange for momentary pleasures and empty platitudes, while malcontents are labelled mentally ill, is pretty daring, and the sort of thing that today would spawn a hundred furious blog posts and a week’s worth of FOX News-generated outrage. This is definitely on the top of my wish list for episodes to be rescued from oblivion.