The TARDIS is swept up in the wake of a superheated plume from the substrate of the Time Vortex, and as the Doctor struggles to control his ship’s flight, Peri has a strange vision of an alien Queen sending her children out to colonise the Universe. The TARDIS then materialises in what seems on first glance to be a street in 1960s London; however, the presence of the Ant Nebula in the night sky indicates that they’re on the far side of the galaxy, 8,000 years in Peri’s future. As the Doctor and Peri explore, they find their way to a wall separating this district from its neighbour; the wall opens up to let a car through, but only Peri manages to get through the gap before it closes. On the other side, she finds herself in a replica of the Los Angeles Skyline Mall from the mid-1980s, and decides to explore on her own.

This is Reef Station One, a space station on the borders of the New Earth Republic. Elsewhere on the station, Joan Bruderbakker, the trophy wife of business executive Charles Bruderbakker, is about to have a makeover, fearing that her marriage will end when she starts to show the signs of age. She has thus decided to treat herself to the Skin Deep process, which is touted as plastic surgery without the surgery. Meanwhile, Joan’s step-daughter, Claudia, who despises the self-centred Joan, decides to indulge herself in a shopping spree. She literally bumps into Peri at the mall, and invites her to the exclusive Eyrie restaurant to make up for the accident. Peri and Claudia hit it off immediately, and Peri learns that most of the Republic’s population is rich, powerful and somewhat indolent. Since this is 8,000 years in Peri’s future, and 8,000 light-years from Earth, 20th-century television broadcasts are only just now arriving in the New Earth Republic, and nostalgia for Peri’s era has become a new fad.

Claudia invites Peri to go out clubbing that night, and as they prepare to return to Claudia’s home, their shopping is loaded into the car by plastic automata known as Synthespians. Originally created to act as extras in Reef Station One’s original television programming, they are now used for all sorts of menial jobs across the Republic, and some of the more advanced models have even taken on leading roles on TV. As Claudia and Peri return to the Bruderbakker mansion, Claudia warns Peri what to expect from her bitchy stepmother -- but when they arrive, Claudia is shocked by the complete change in Joan’s personality. Joan has suddenly become the perfect hostess and stepmother, and Claudia, weirded out by the sudden transformation, decides to get out of the house as soon as possible. Once Claudia and Peri have gone, Joan dismisses the servants and personally cooks dinner for her husband, without burning it. Charles is also startled by the change in Joan, but is even more taken aback when she sweetly asks him to sign over controlling interest in his company to Walter J. Matheson III, the most powerful businessman in the New Earth Republic. Charles flatly refuses to do so, and Joan therefore takes other measures.

Meanwhile, the Doctor makes his way to a pub, hoping to learn more about the world he’s ended up in. There, he meets washed-up actor Marcus Brooks, whose career took a nose-dive after the soap Executive Desires was cancelled by the network. The show has just been revived, and Marcus, desperate to make a comeback, signed his contract before reading the script -- and learned too late that Dominique Delacroix, who holds a grudge against Marc for once having turned down her advances, had arranged for his character to be killed off in Act One. The Doctor shows an interest in order to learn more about Reef Station One, and he thus learns that this pub is located in a Wannabe district populated by struggling actors. He also learns that the districts on the station have been placed in different time zones; thus, even though it seems to be late at night in this district, it’s actually only 1:00 in the afternoon. This may be why the Doctor, who is sensitive to temporal disruptions, is having trouble concentrating. As he speaks to Marc, he notices that the pub’s television is playing an episode of Dixon of Dock Green -- which is in impossibly pristine condition for a programme that was first broadcast 8,000 years ago.

Elsewhere, Walter J. Matheson III leaves his offices in the WJM Tower to collect a box containing a glowing sphere, the last component needed to complete his master plan. However, his allies then contact him via the sphere to warn him of a possible complication. While waiting for the main plan to tick ahead, Matheson decides to deal with August deValle, the chairman of Republica Communications Inc. On paper, the New Earth Republic is run behind the scenes by nine powerful business leaders, but Matheson has gradually been taking over his rivals’ companies, and the Nine are slowly becoming just One. deValle is aware of Matheson’s ambitions, and refuses to sell his interest in Republic Communications -- and Matheson therefore invites deValle to the WJM Tower, and calls in the services of a particularly persuasive employee...

Marc invites his new friend out to see a movie while he can still afford to enjoy himself. On the way, he sobers up and realises that the Doctor isn’t an out-of-work actor at all; the Doctor claims to be an intergalactic policeman of sorts, and swears Marc to secrecy. When they arrive in Entertainment District 1, they bump into a panic-stricken man who claims to be surrounded by the soulless. When a policeman dressed like a traditional London bobby wanders up, the frightened man suffers a heart attack. Paramedics arrive and cart the man away for treatment, but soon afterwards, the policeman receives word that the man has died. He also identifies the dead man as August deValle. Unable to do anything more, the Doctor and Marc enter the theatres and watch a restored edition of George Pal’s The Time Machine, which the Doctor notes has been restored to an impossible level of clarity, considering that the original broadcast traversed 8,000 light-years of space full of exotic particles and energy fields. The Doctor decides to investigate, and he and Marc trade phone numbers so they can keep in touch. Marc doesn’t realise that the Doctor’s mobile phone is actually August deValle’s, which the Doctor picked up from the ground where deValle fell. And neither yet know that deValle’s company is now a subsidiary of WJM Inc.

The Doctor, feeling oddly exhausted, returns to the TARDIS to conduct some research into the New Earth Republic. The Republic was founded by refugees from a galactic civil war whose ships went off-course into an isolated sector of space, unpopulated, rich in mineral resources and cut off from the rest of the galaxy by a barrier of exotic energy fields. The colonists founded a near-utopian society with no want or poverty, but were then faced with the problem of what to do with their lives. The problem was solved when a technician trying to clear up interference in the Republic’s sub-etheric communications relays discovered that the “interference” was in fact ancient television signals. The people have since become obsessed with 20th-century TV and have founded whole societies based on the programming. But the Doctor can find no explanation for how the Redux process can restore such badly degraded signals to such impossible levels of clarity, and thus decides to visit WJM Inc. in person.

Claudia and Peri go clubbing at Mandrake’s, where Claudia introduces Peri to her old friend, Marcus Brooks. Peri enjoys the night out with her new friends, but when they return to the Bruderbakker mansion in the early hours of the morning, they find Claudia’s father dead and Joan sitting next to him, holding a bloodstained knife. Joan remains placid throughout the ensuing panic, screaming only when Marc uses his mobile phone to call in the emergency services. The police arrive and take Joan from the house, and when they question the others, Peri learns that someone has provided them with false information that saves her from trying to explain how she ended up here. The police then arrest Marc, claiming that he’s under suspicion of committing acts of indecent exposure. Marc has little choice but to accompany them, but, still believing that the Doctor is some sort of policeman, Marc gives Claudia his mobile phone, telling her to call the man at the bottom of the speed-dial listings. As the police drive him away from the mansion, however, he notices that they’re driving in the wrong direction, and when he questions them, they unexpectedly beat him unconscious.

The Doctor sets up a meeting with Redux’s PR representative, Miss Glove, at the WJM Tower, and eventually drives her from the room with his intricate technical questions about the process. Matheson himself then visits the Doctor, and apparently catches him entirely off-guard by making sly allusions to time travel. He also refers to Redux as “thinking celluloid,” but refuses to explain further. The Doctor retreats, obviously aware that Matheson is just toying with him. In fact, he’s not as disoriented as he wants Matheson to believe, but he’s still having trouble concentrating and is no closer to understanding the threat he’s facing. He then receives a phone call from Claudia informing him that Marc is in trouble, and is reunited with Peri when he responds. In the interim, Claudia has called up the precinct house -- and has learned that they never received Marc’s phone call in the first place. The “policemen” who arrived in response have cleaned up the crime scene and vanished, removing all evidence of the murder and taking Marc and Joan with them. Peri recalls seeing a set of business papers at the crime scene, and when the Doctor investigates, he finds that Charles Bruderbakker apparently signed control of his company over to WJM Inc. at 6:00 a.m., over an hour after he died.

Matheson visits the set of Executive Desires to speak with Dominique Delacroix about their master plan. Matheson does not find the role of businessman challenging enough in the complacent Republic, and intends to take his business out to the rest of the galaxy -- whatever the cost. Meanwhile, Marc recovers from his beating to find himself being taken to a laboratory of sorts by the arresting policemen, whom he now realises are Synthespians. Joan is waiting for him there with a glowing purple sphere which begins to take over Marc’s mind...

While Claudia and Peri shower and change, the Doctor does some research and discovers that Matheson now owns six of the original nine super-corporations -- and through deValle’s and Bruderbakker’s companies, he owns 100% of the Republic’s mobile phone network, which uses sub-etheric beams to transmit messages through the blanket of exotic particles that have cut the Republic off from the rest of the galaxy. Matheson also owns the companies that control Redux, Skin Deep, and the 3-D televisions known as Living Space. As Joan’s personality change occurred after her visit to Skin Deep, the Doctor decides to investigate it with Claudia, and sends Peri to the WJM Tower to keep Matheson on his toes. On their way to Skin Deep, however, Claudia realises that her chauffeur, Sean Brady, is driving them way off course through a warehouse district. The Doctor pulls Brady away from the steering wheel, and the car crashes before its automatic guidance systems can kick in. The Doctor and Claudia escape unharmed, but Brady goes through the windshield -- and is revealed to be a plastic replica. As Brady’s hand drops away to reveal a gun, the Doctor finally realises that the so-called Synthespians are in fact Autons.

The Auton-Brady chases the Doctor and Claudia through a nearby warehouse, smashing straight through the stacked crates to get to them. Just as it catches up to them, however, someone calls Claudia on her mobile phone, and the Auton twitches and collapses, dead. The Doctor hot-wires a nearby robot delivery truck and sets off for the WJM Tower with Claudia, realising that he’s miscalculated and sent Peri into far greater danger than he’d anticipated. The Nestene Consciousness has been attacking his mind ever since he arrived on Reef Station One, which is why it’s taken him so long to realise what he’s facing. Once he’s shored up his mental defences, he explains the nature of the enemy to Claudia; the Nestene Consciousness is the offspring of the Great Old One known as Shub-Niggurath, and the core of its gestalt consciousness is located on the planet Polymos, from which it sends out its seeds to colonise other planets in the galaxy. It seems that the sub-etheric beams from Claudia’s mobile phone can sever the telepathic link between the Consciousness and its Auton servants -- but this is because Claudia recently dropped her phone in the swimming pool. When the Doctor examines it, he finds that its shielding coils have shorted out. Modern mobile phones have more effective shielding, and will thus be useless as weapons, especially since Matheson now controls the entire network.

Meanwhile, Matheson is receiving disturbing news. The Nestene Consciousness deliberately brought the Doctor to Reef Station One, seeking revenge, but now he’s evaded its clutches and it’s blaming Matheson for this. Worse, the Auton that chased the Doctor and Claudia through the warehouse inadvertently smashed the very equipment that Matheson’s engineers had requisitioned from Republica Communications, and the final phase of the plan is in jeopardy.

Marc awakens to find himself in an Imperial Hotel suite. Assuming that he’s in one of the Entertainment Districts, he breaks out of the suite, only to find the streets of the district unfamiliar and deserted. Searching for a way out, he follows a distant figure to the district wall, only to be hit on the head and knocked out when he tries to leave. When he next awakens, he finds himself strapped down in a laboratory, where Matheson is there to gloat. He’d originally arranged for Marc to be put out of the way to avoid publicity over Charles Bruderbakker’s death, but now he has another purpose in mind for him. When Marc learned of his character’s fate on Executive Desires, he made some ill-advised comments about Dominique Delacroix’s affairs with Matheson, and Matheson heard every word. He thus intends to use Marc in a special dress rehearsal for the first episode of the new Executive Desires...

Peri gets into the WJM Tower by posing as a member of Claudia’s legal team and wanders the building, relying on her confident poise to keep people from asking whether she belongs there. Eventually, she deduces that the Tower is hollow, and finds a secret panel leading into a quad at the centre of the Tower; there, she sees a gigantic crystal, 50 storeys high, but is confronted by three Synthespians before she can investigate. Matheson arrives and stops the Synthespians from killing her, and he and Dominique then taunt Peri over her failures, both as an adventurer and as a person. When Peri caught a glimpse of the Nestene Consciousness in the TARDIS, it looked into her mind as well. Claiming that Peri is a born victim, Matheson and Dominique force her to undergo the Skin Deep process -- which implants plastic beneath the surface of the skin, enabling the Nestenes to control the mind and body of the victim.

The Doctor and Claudia hop a tour bus to the WJM Tower, only to find the Synthespians waiting for them. The Synthespians take their prisoners to the set of Executive Desires, where Matheson has Claudia sent for Skin Deep processing and uses a Living Space television to show the Doctor what’s happening on Polymos. To the Doctor’s horror, the planet is under attack by a fleet of war-TARDISes; the Time Lords are making a concerted effort to destroy the Nestene Consciousness, and Matheson has offered to help it escape. Dominique brings out Peri, Marc and Claudia, who have all undergone the Skin Deep process, and forces them to act out the opening scenes of the new Executive Desires for real; unless the Doctor agrees to help Matheson, his friends will all kill each other.

The Doctor holds out until the melodrama reaches its climax, but he gives in when Claudia and Peri’s characters begin to struggle for a loaded gun, agreeing to help Matheson but refusing to let the Nestenes into his TARDIS under any circumstances. Dominique reverses the Skin Deep process, causing the plastic to flow out of its victims’ pores. Once his friends are free, the Doctor triggers Claudia’s mobile phone; the signal does not affect Dominique, but the less advanced Synthespian guards freeze up, enabling Claudia and Peri to escape. However, Marc then reveals himself to be another advanced Replica, and the Doctor thus remains a prisoner.

Claudia and Peri steal a cab, using the mobile phone to disable its Synthespian driver; however, the phone’s battery is running low, and they will soon be weaponless. Claudia switches off the cab’s auto-guidance systems and drives back to her mansion; there, she switches the auto-guidance systems back on, and she and Peri bail out of the car and let it drive up to the front doors on its own. As they’d feared, the cook and major-domo emerge from the house and blast the cab into oblivion; like Brady, the rest of the household staff have been replaced with Replicas. Peri and Claudia slip in through the back door, evade the house staff and lock themselves in Charles’ study, which has been fully shielded against intruders. There, Claudia removes the company’s old, poorly shielded mobile phones from their display cases and begins to charge them.

Back at the WJM Tower, Matheson shows the Doctor the crystal spire, a giant receiver through which Matheson intends to download the entire Nestene Consciousness into a new host. He then takes the Doctor to his office for a private conference, and, once inside, reveals that the walls, ceiling and floor are made of a duralinium-matricite alloy that can withstand a direct attack from the Autons and shield against telepathic signals. The Doctor had believed Matheson to be a Replica, but he is in fact still human; when the first Nestene meteorite swarm landed on Reef Station One, the sub-etheric radiation in the Republic left it too weak to control Matheson’s mind, and he was able to strike a deal with it. He then had a matricite web woven into his brain to prevent them from reading his mind and learning his true intentions. He has tired of the lack of challenge in the indolent Republic, and believes that the people of the inner galaxy, who have suffered through terrible wars and dictatorships, represent the true pioneering spirit of humanity. He thus intends to sacrifice the Republic to the Nestenes and then summon the Galactic Union to the rescue, giving them a common enemy to fight -- and giving himself a more challenging target market. Everything was on schedule until the Brady Replica chased the Doctor and Claudia through the warehouse, destroying the equipment that Matheson’s scientists needed to complete the machine that will download the Nestene Consciousness. Now Matheson needs the Doctor to help him finish the machine. If he refuses, he and his friends will be killed, and the plan will go ahead in any case -- but with much greater bloodshed, since Matheson will have to rush his work.

The Doctor, angered by Matheson’s callousness, claims that the Nestenes will be too firmly established to defeat by the time the scientists of the Union work out how to penetrate the Great Barrier. However, he has little choice but to co-operate. Satisfied, Matheson puts him to work and leaves Marc’s Replica to guard him. Like the other Replicas, this one drawing on Marc’s brain-print to mimic him; the real Marc is still alive in suspended animation elsewhere in the WJM Tower. However, this Replica is more advanced than any other model the Doctor has encountered to date; it had to be, in order to fool him so completely. In fact, it’s so advanced that it shares Marc’s bitterness about being reduced to a series of “third vampire on left” roles after having worked on such a popular soap. The Doctor points out that Marc is now in a perfect position to take his revenge against Dominique...

The Replicas in the Bruderbakker mansion report that Claudia and Peri have barricaded themselves in the den, and Matheson thus switches on the transmitters, activating his secret weapons. The Living Space television sets used in the Republic extrude plastic to generate 3D models of the broadcast images; in the Bruderbakker den, the television switches itself on, and tiny 3D soldiers from a war documentary march straight off of the platform and open fire on Claudia and Peri. The girls barricade themselves in the bathroom, but as the soldiers attempt to shoot through the door, the plastic bathroom furnishings attack the girls, including the shower curtain and the electric toothbrush. Meanwhile, the Doctor has sent Marc away, ostensibly to fetch some necessary tools, and is now being guarded by a less sophisticated Auton model. When Matheson tells the Doctor that he’s had to switch on the transmitter momentarily, the Doctor is able to investigate without his guard noticing anything amiss. He soon realises what’s happening and jams the signal, enabling Claudia and Peri to escape. Instead of fleeing to the TARDIS, however, they collect the recharged mobile phones and plan to join the Doctor at the WJM Tower.

Matheson catches the Doctor interfering in his plans, and triggers a signal that will activate Autons all over Reef Station One; he no longer needs the station, and wants to conduct a “dress rehearsal” for the chaos that will soon engulf the Republic. All across Reef Station One, Synthespians and other plastic objects turn murderous; everything from faux pearl necklaces to breast implants becomes a killer. The Doctor is appalled by the carnage, but has little choice but to finish his work. Meanwhile, Matheson fetches Dominique from the set of Executive Desires; the first episode is about to go out live, awakening Autons throughout the entire New Earth Republic, but the role of Majeste Parnell Partington Wilby Poindexter Raven will be played by a Synthespian. Dominique has other work to do; she’s the most advanced Replica of them all, with a neural net capable of containing the entire Nestene Consciousness. Soon, she will be the Nestene Queen incarnate. The Doctor is forced to begin the download, and as the Nestene Consciousness begins to transfer itself into Dominique’s Replica, the Doctor realises that Matheson is in love with her -- or rather, with the plastic, “ideal” version he’s created. Once the Nestene Consciousness is in control of the Republic, Matheson intends to negotiate a peace between it and the human race, with Dominique, the Nestene Queen, at his side.

Claudia and Peri fight their way past Joan and escape from the Bruderbakker mansion; however, Claudia realises that Peri is growing sick of her life of “adventure”, and offers to let her new friend stay with her on Reef Station One. On their way to the WJM Tower, they see chaos in the streets as the Synthespians slaughter the human population, and see a tentacled Nestene energy creature forming around the broadcast antenna. There are Autons waiting for them at the WJM Tower, but Peri realises that the Autons could have killed them at any time and convinces Claudia to surrender. The Autons take their prisoners to Matheson’s office, but don’t bother to confiscate their mobile phones, as they’ve already proven to be useless against Dominique. But before Matheson realises what the Doctor’s doing, he uses Peri’s mobile phone to call Marc’s Replica. The Replica has made its way to the storage facilities where the Replica’s human templates are kept in suspended animation -- and, just as the Nestene Consciousness finishes downloading itself, Marc’s Replica frees the real Dominique from her cabinet, severing the link between the original and her Replica. Dominique’s Replica freezes up, the entire Nestene Consciousness now trapped inside its body as it mindlessly repeats Majeste’s lines from Executive Desires.

Matheson hysterically orders the Doctor to take him back in Time to put things right, but the real Dominique storms into the office with the real Marc, and through sheer glamorous star power reduces Matheson to a quivering wreck, showing him up for the petty little man he is. Defeated and humiliated, Matheson shoots himself in the head. The Doctor explains that the Nestenes had to make Marc’s Replica realistic enough to fool him, but they made it so realistic that the real Marc’s personality managed to overwhelm the Nestene influence and cause the Replica to switch sides. The Replica eventually collapsed, unable to handle the strain, but now the Nestene Consciousness is trapped forever in a useless body.