Arnold Baynes and his wife Lorraine have attacked a freighter registered to the galactic bank, circumvented its safeguards and blown open the vault to recover something more valuable than mere treasure -- the body of Davros. Before loading Davros aboard their interceptor, Arnold kills his pilot and leaves the body in the vault to cover what he and his wife have done. He then pilots the interceptor back to their home system himself, although it switches over to automatic flight control once it enters the planet’s atmosphere. All of the top-notch medical equipment aboard the interceptor is telling Lorraine that, despite everything, Davros is dead.

The Doctor has just arrived on the same planet in response to a call from Willis, a journalist of his acquaintance. In the wilderness outside the five-mile-high TAI Dome, Willis introduces the Doctor to computer technician Kimberley Todd, who has unearthed a memo which indicates that TAI is planning to close down all of their mining colonies. With an effort, most of the mines could still be run at a profit, and closing them will put billions out of work. As the Doctor discusses the matter with Willis and Kim, a ship comes in to land and a secret hangar opens up practically beneath their feet. The Doctor impulsively rushes into the hangar to investigate, followed by the others, who are surprised to see Arnold Baynes himself -- the CEO of TAI, and one of the richest men in the galaxy -- emerge from what had appeared to be a pirate ship, a raider built for a quick attack and sudden getaway. Baynes and his wife then wheel the body of Davros out of the raider, and the enraged Doctor breaks cover to confront him, leaving Kim and Willis with little choice but to slip away while the guards are distracted.

Despite the evidence of the medical systems, Davros is alive and dreaming of significant events on his life. He recalls Scientist Ral speaking to the Kaled Elite, who founded their nation on the principles of self-reliance and genetic purity -- yet who couldn’t bring themselves to kill him, even after the terrible injuries inflicted by the Thal shelling. He recalls waking after the attack to find a somewhat nervous Ral hovering over him, and screaming as he saw his own horrifically scarred face. He recalls being found by two radiation-suited rescue workers after the attack, and, in his delirium, calling out for a woman named Shan...

Baynes questions the Doctor, but the Doctor angrily questions him right back. When he learns that Baynes’ wife is a historian named Lorraine Baynes, he recognises the name of a future Oxford professor and an author of books reinterpreting the historical context of the Daleks and their creator. Realising that the Doctor genuinely believes that Davros can be revived, the intrigued Baynes takes him to the medical centre where Lorraine is tending to Davros’ body. Just as the Doctor had feared, Davros has begun to show signs of life. The Doctor desperately tries to convince the Baynes to let Davros slip back into full suspended animation, but it’s too late; the flat-lining Davros bursts back to life within seconds, and the Doctor finds he can’t bring himself to pull the switch and end Davros’ life himself. Once again, Davros is alive and awake.

Meanwhile, Willis is trying to understand why Arnold Baynes would want the body of the Daleks’ creator. There’s a huge market for Dalek memorabilia, and Willis believes that Baynes only cares about profit; could he have stolen the body of Davros simply to sell it to a collector? Searching for a way out of the mines, Willis and Kim stumble across evidence that Baynes is certainly up to something; several levels beneath the hangar, a secret, automated production line is constructing an army of robots.

Arnold and Lorraine introduce themselves to Davros, and as the appalled Doctor listens, Baynes reveals that they’ve revived him to offer him a job as the head of R&D for their company. The human race dominates this galaxy, and within generations they will have used up its resources -- and they don’t yet have the technology to travel between galaxies. They need to develop radical new ways of thinking in order to expand and stay competitive, and that’s why they’ve come to Davros. Baynes plays a promotional video which lays out TAI’s agenda -- to supply the human race with the goods and services they need, before they know they need them. The Doctor dismisses the video as corporate propaganda, but Davros seems impressed and understands that, while the vision expressed is not reality, it’s an ideal which the company strives for. He thus accepts the job offer. Fearing the consequences should Davros gain a foothold of power, the Doctor offers his own services in Davros’ place. Much to the Doctor’s surprise, Davros concedes that the Doctor is, at the very least, his intellectual equal. However, rather than choose between the two of them, Baynes decides to hire them both on a trial basis. It seems that the Doctor and Davros will be working together.

The next morning, the Doctor is woken from a sound sleep by the disembodied voice of his new personal organiser, which was inserted into his inner ear while he slept. The Doctor orders it to let him sleep for another 25 minutes, giving him only five minutes to wake up, eat breakfast and get to work. As soon as he gets the chance, he sticks a screwdriver in his ear and shorts out his organiser. Davros has arrived at work two hours early, but as soon as the Doctor shows up he reconfigures the alpha matrix which Davros has constructed, burning it out within seconds and then blaming Davros for failing to build in adequate safety precautions. Baynes leaves the Doctor to build a new alpha matrix from scratch, and the Doctor asks the fuming Davros to make himself useful by fetching some tea.

Baynes asks his wife to research the history of the Doctor so they can determine whether he poses a threat. He then attends his scheduled interview with Willis, expecting to be amused by the independent journalist’s childish beliefs about the way the galaxy works. Baynes believes that the corporations are there to provide people with what they need for a better life, and that he has a duty to anticipate those needs so his R&D department can develop products in time to meet the demand. Willis, on the other hand, believes that the corporations control people’s lives, and that they use advertising and propaganda to condition consumers into wanting only what the corporations have to offer. Willis questions Baynes about his hiring of Davros, but Baynes smoothly defends himself, pointing out that Davros is the greatest scientific mind in the galaxy, and that even though he did create the Daleks, they turned on him almost at once. Willis finally provokes a reaction by asking Baynes if he intends to close down the mining planets; Baynes, angered, accuses Willis of spreading gossip and rumour rather than reporting the truth, and destroys Willis’ recorder when Willis refuses to reveal his sources. Willis, shaken, demands that Baynes let him go, but Baynes insists that Willis remain in the dome so they can conduct another interview once Willis has “calmed down.”

Davros fears that the Doctor intends to destroy him, but he must concede that the Doctor has good cause to suspect his motives. However, he insists that he is genuinely trying to reform. He and the Doctor share a long history, and perhaps if things had been different, they could have been friends. As it is, Davros has spent decades in suspended animation, and he was conscious for all of it -- held in total sensory deprivation for longer than most people’s lifetimes, forced to relive his past over and over again in every terrible detail. He claims that the process has shown him just how petty and meaningless his desires are -- but the Doctor remains sceptical, and vows to keep an eye on Davros.

Baynes then arrives to pass on a lunch invitation from his wife to Davros. The invitation doesn’t extend to the Doctor, but Baynes does offer to give him a tour of the dome’s computer centre. All life within the dome is regulated the computer centre, which is effectively a fortress within a fortress. Baynes assigns Kim Todd to show the Doctor around, unaware that they’ve already met, and Kim takes the opportunity to tell the Doctor that she and Willis have found a secret lift leading between the dome and a secret production line which doesn’t appear on any of the computer databases. The Doctor arranges to meet Kim and Willis after Kim’s work shift ends, in order to investigate further.

Davros is taken aback to find that Lorraine regards him with admiration rather than fear; she has interpreted the facts of history somewhat differently than other historians, and believes Davros to be a great scientist and a man of destiny. Davros admits that he’s trying to put his past behind him, but his past is exactly what fascinates Lorraine; she wants to write Davros’ definitive autobiography to clear his name so the rest of the galaxy will see him the way she does. However, Davros is out of his depth in Lorraine’s world, and the sumptuous banquet which her chef has prepared is like nothing he’s ever seen. On the war-torn world of Skaro, food was limited and no resources could be wasted; Davros recalls an incident in which he horrified one of his female colleagues by casually revealing that their food pills were processed, not only from waste vegetable matter, but from the bodies of the dead. He does not tell Lorraine -- yet -- who that female colleague was, but he does admit that by his time, nobody could remember just how the war had started, and that they fought simply because that was all they could do. Yesterday was the first time in Davros’ life when nobody was trying to kill him... but he still doesn’t feel safe as long as the Doctor is around.

TAI’s stock continues to rise, but while Baynes is satisfied, the Doctor warns him that Davros could still destroy everything he’s worked for if Baynes isn’t careful. Though Baynes doesn’t admit aloud that the Doctor has given sound advice, he does nevertheless check on the status of the interceptor ship, in case he needs to leave the dome in a hurry. Meanwhile, the Doctor and Davros complete their work on the alpha matrix, finishing in a day what Baynes expected would take months. Davros then claims that he intends to solve the galactic famine which Lorraine mentioned during their meal, and the Doctor can find no objections to letting him tackle the problem. Disturbed nonetheless by Davros’ sudden humanitarian interest, the Doctor goes off-shift to discuss the problem with Willis and Kim, but Willis remains convinced that Baynes is the real threat. The Doctor concedes that the presence of a secret production line is strange, and agrees to investigate.

Davros finds himself reliving a moment from his past history, and although he snaps out of his reverie he is disturbed by the vision. Elsewhere, Baynes discusses Davros with his wife, who is coming to see him as crippled not by his bodily injuries but by his upbringing in a world at constant war. It would be easy for Davros to clone a new, undamaged body for himself and copy his memories into it -- but Baynes points out that few people take advantage of the technology to do so. Even a perfect copy would only be a copy, and the original person would still be dead. Thus, Davros remains alive in his crippled, twisted body, and lets his pain drive him forward. Lorraine is fascinated by Davros’ drive, but her husband is concerned by it; the Doctor’s warning has hit home, and Baynes advises Lorraine to be careful around Davros.

Baynes finds Davros recovering from his waking dream, which Davros dismisses as a temporary chemical imbalance in the memory centres of his brain, easily corrected by his life-support system. He has analysed the galactic economy, and believes it to be a chaotic system in the scientific sense -- and far less efficient than Skaro’s war-time economic system. Noting that Davros seems to have turned across the corporations, Baynes mentions Willis and his beliefs in passing, but he is then called to deal with the malfunctioning robot on the assembly line. The robot has targeted the Doctor, who has sent Willis and Kim to safety while he draws it off. Baynes and his security guards arrive and destroy the robot before it can kill the Doctor, but Baynes blames the Doctor for somehow provoking the attack and has him removed.

Lorraine finds Davros analysing stock market reports for the last fifty years; as he suspected, the system is scientifically chaotic, which means that even changes which appear random are in fact predictable. In other words, he’s calculated a formula which enables him to predict the result of any exchange of stock. Lorraine realises that this formula could make Davros the most powerful man in the galaxy, but she doesn’t understand the mathematics when he tries to explain his reasoning to her. Realising that nobody in the galaxy can keep up to his thinking, Davros inadvertently refers to Lorraine as “Shan” while distracted. He covers this lapse, and Lorraine promises not to tell her husband about Davros’ formula until Davros has decided what he wants to do with it.

The next morning, the Doctor wakes to find that another personal organiser has been inserted into his ear -- and that he’s been locked in his room while Baynes evaluates his work for the company. Elsewhere, Baynes discusses the Doctor’s erratic behaviour with Lorraine and Davros; he thinks it would be safer to have the Doctor deported, but Lorraine thinks it would be best to have both the Doctor and Willis killed before they find evidence to link them to the attack on the freighter. However, Davros claims that the Doctor could still prove useful if he can be controlled, and advises Baynes to keep the Doctor under constant surveillance.

The Doctor grows tires of waiting and asks his organiser to link to the food dispense and deliver an unusual breakfast -- a five-inch length of copper wire, with which he plans to short out the door controls. Before he can do so, Baynes arrives to discuss the security breach on the production line. The Doctor claims that Davros must have programmed the robot to become hostile, but Baynes provides him with proof that the fault lies in a programming error made by the Doctor himself. Somewhat chastened, the Doctor demands to know why Baynes is building mining robots with such advanced intelligence if he plans to close his mining colonies, but Baynes explains that the plan was just a random idea thrown out by a focus group and dismissed as foolish. He is amused to realise that the Doctor only came here because someone found a discarded memo and panicked unnecessarily. The robots are only meant to think for themselves, making leaps of logic and intuition beyond humanity’s reach; in other words, just what Baynes said he wanted of them in the first place.

Davros contacts Willis, claiming to have found an atomic bomb in Baynes’ possession. It’s illegal for private individuals to own such weapons, and Davros gives it to Willis as proof of Baynes’ misdeeds, assuring Willis that the trigger has been removed. Davros also reveals that he has developed an equation which could enable anyone, anywhere, to predict the outcome of any exchange of stock; if Willis uses his news service to spread the equation to everyone in the galaxy, then the stock market will become meaningless and the corporate infrastructure will collapse, leaving the way clear for Davros to implement a new economic model. Willis’ initial delight soon turns to horror, as Davros reveals that his model is based on a war-time economy; criminals will be executed or put to work as slaves, ordinary citizens will work in armaments factories and produce children, and only those with special aptitudes will become the galactic Elite. Horrified, Willis storms out on Davros, contacts the Doctor and asks to meet him in the mines, where they can’t be observed -- unaware that Baynes is standing next to the Doctor, listening to every word he says.

Davros goes to the dome’s computer centre, and on the way, he meets Kim Todd and learns that she can upload files from the secure company database onto the galactic data net -- if given permission by someone in authority. Satisfied, he sends her about her business while he deals with some loose ends. Lorraine then arrives, and notices that Davros is watching Kim as if she reminds him of someone. This time, Davros tells Lorraine about the woman named Shan, the most beautiful and intelligent Kaled whom Davros had ever met. It was Shan who first wrote a paper suggesting that the weapons of war were destroying Skaro, and that even if the Kaleds wiped out the Thals they would inherit a planet incapable of supporting life. Since the Kaleds and Thals were competing for a single ecological niche, co-operation was a biological impossibility, and it therefore seemed that the Kaled race was doomed one way or another. However, Shan proposed a radical solution to the problem -- which she termed “the Dalek solution.”

Davros is quick to point out that Shan merely proposed the idea of the Daleks, and that he is still the one who put theory into practice. Lorraine, trying to understand his motivations, questions his feelings for Shan, and realises that Davros is contradicting himself. He claims to have felt nothing for her, and insists that his life-support system regulates his body’s neurochemical balance to neutralise unnecessary emotions -- but he knew Shan before the bombing which placed him in the chair.

Davros goes on to explain that he presented Shan’s paper to the Kaled Council, but didn’t give her credit for it. He also admits that he modified her conclusions; though he admired her intelligence and drive, he also feared that the Council would react badly if they realised they were authorising the creation of a new species which would one day take the Kaleds’ place. Shan was upset, but not as upset as Davros when he learned that she had become involved in a romantic relationship with Councillor Valron. Davros claimed that her work was suffering and that Valron was suspected of sympathising with the Thals, but Shan accused him of inventing accusations against Valron. She didn’t yet realise why Davros was really so angry with her...

Davros still insists that he had no feelings for Shan himself, and, to Lorraine’s horror, he reveals that he planted evidence identifying Valron as a Thal sympathiser, and had him and associates arrested and executed -- including Shan. He claims that he did it because Shan was planning to take credit for her own paper, and that he was only acting to secure his position as Skaro’s greatest scientist -- but Lorraine knows otherwise. She is finally seeing Davros for the monster he is, but it’s far too late. By talking about his past with Lorraine, Davros has come to understand that the same patterns will always repeat in his life. He claims that his guilt and shame were nothing but neurochemical reactions which made all of his subsequent “achievements” with the Daleks possible -- and he no longer believes that it’s possible for him to change his ways. And now the time has come for him to destroy his enemies once more.

Baynes accompanies the Doctor deep into the mines, past a shaft more than fifteen miles deep, to find out what Willis has to say. Willis, though furious with the Doctor for bringing Baynes along, must admit that the Doctor was right about Davros all along; however, while he claims that Davros’ vision of the galaxy as a giant concentration camp is what Baynes has been working towards as well, Baynes insists that he really does want to improve people’s lives by supplying them with what they want. But the argument is interrupted by Davros, who installed a speaker on the atomic bomb which he gave to Willis, and which he built himself. He lied when he said that it belonged to Baynes -- and he lied when he said that it had no trigger. Lorraine is unable to prevent Davros from triggering the detonation sequence, but the Doctor grabs the bomb and flings it down the 15-mile-deep shaft. It falls far enough before it detonates for the Doctor and the others to survive the explosion -- but that’s the least of the bomb’s effects...

Davros orders Kim to evacuate everyone but himself, herself, and Lorraine from the computer centre, and then orders the hysterical Lorraine to transfer her executive power to him; she does so, but realises too late that as Arnold is now believed to be dead, she has just made Davros the new CEO of TAI. She also realises that he’s condemned everyone outside the computer centre to a slow and painful death, as the radiation from the nuclear explosion is rising up into the Dome. The computer centre is sealed off, so she, Davros and Kim will survive -- but hundreds of thousands of workers, the old management’s most loyal employees, are about to be purged as Davros’ reign begins.

The explosion has cracked the barriers between the mines and an underground lake, and water floods through the tunnels, washing away the radioactive particles and thus saving the Doctor, Baynes and Willis. Unfortunately for Willis, however, he and Baynes have been separated from the Doctor -- and Baynes takes this opportunity to ensure that the journalist will not be able to reveal the truth about his activities. When the Doctor finds Willis dead, he apparently assumes that his broken neck was suffered when the mines collapsed. He is then reunited with Baynes, and isn’t terribly surprised when his inner-ear organiser helpfully identifies Baynes as the “former” CEO of TransAlliedInc. Above their heads, Davros is in command...

Davros orders Kim to transmit his stock equation to the galactic data net, but Kim hands the disc to Lorraine for safekeeping, aware that civilisation will collapse if she does what Davros wants. However, Davros’s computer-enhanced senses detect that Kim is lying when she claims to have sent the message, and he punishes her by transmitting a high-frequency sound through her earpiece. Lorraine reminds him that he still needs Kim to operate the communications console, and he therefore switches off the sound before it shakes Kim’s brain apart and grants her some time to recover. He then records a message for all regional managers of TAI, outlining the company’s new operational plan; however, he’s forced to re-record his message when Lorraine points out that it included the background sound from the dome’s security monitors, the screams of hundreds of thousands of people dying in agony from radiation burns, which Davros hadn’t even noticed. Davros then orders Lorraine to liquidate all assets of TAI and put the money into armaments and mercenaries, ensuring that TAI will be poised to seize control once Davros’ equation causes the collapse of the galactic stock market.

The Doctor and Baynes find their way out of the mines, emerging within walking distance of the TARDIS. The Doctor takes Baynes directly into the supposedly impenetrable computer centre, where the hysterical Lorraine reveals what Davros is doing. Before confronting Davros, the Doctor attempts to activate the self-motivated robots on the secret production line and send them to rescue the suffering occupants of the Dome. However, Baynes refuses to wait, and sets off to confront Davros himself.

Davros is again reliving memories from his past, this time of the day when he visited Shan in her execution cell. He claimed that he’d come to gloat, but she realised that his reasons for having her arrested were nonsense; she could never have supplanted him or taken his place in history. Davros denied what she was saying, but she understood at last what he felt for her -- and that he couldn’t even admit it to himself.

Davros snaps back to the present when Baynes bursts into the room and holds him at gunpoint -- but Baynes doesn’t shoot him yet. TAI will be finished after word of what’s happened here gets out, but Baynes intends to recover by using Davros’ stock market formula to regain his fortune. But Baynes makes a fatal mistake when he tells Davros that there’s a secret lift leading out of the computer centre, and that only Baynes knows the code. Davros tortures the code word out of Baynes by firing electrical bolts out of his body somehow, but then slips into another memory fugue -- one in which the Doctor is standing before him, taunting him and claiming that his chair’s self-repair circuits are malfunctioning, causing him to hallucinate. Davros manages to pull himself together as the real Doctor enters the room, and orders him to surrender the disc with the stock market formula or see Kim suffer and die. However, the Doctor grabs Baynes’ gun and shoots the communications console. Davros takes Kim hostage, using the poison injector which he was given on Skaro so long ago to force her into the lift. Baynes had already had the interceptor readied in case he needed to leave in a hurry, and Davros intends to flee from the planet and then use the interceptor’s console to transmit his formula to the galaxy.

The Doctor shorts open the doors of the lift with the copper wire he’d ordered for breakfast, and slides down the shaft to meet Davros at the bottom. Davros tries to kill the Doctor with a high-frequency transmission through his earpiece, but the Doctor’s metabolism is heartier than a human’s, and the earpiece shorts out first. The Doctor then reveals that the mining robots are decontaminating the dome as they speak; many have suffered and died, but many have been saved. Davros may claim to hold the power of life and death, but he can’t give life -- and he can’t even kill himself, even though he suffers from terrible guilt and has kept the poison injector ever since it was given to him. It is the Doctor who holds the power, not Davros.

Enraged, Davros boards the interceptor, taking Kim with him as a hostage. The Doctor is unable to stop him from launching the ship, but Lorraine then arrives and reveals that they can still control its flight as long as it remains in the planet’s atmosphere. The Doctor tries to bring the ship back in to land, but Davros realises what’s happening and interfaces directly with the flight computer via his chair. Kim realises that the Doctor is afraid to act while she’s on board the ship, and before Davros realises what she’s doing she grabs his poison injector and uses it on herself, thus depriving him of his hostage. The Doctor sadly activates the ship’s hyperdrive, and as the ship crashes into the planet’s surface, Davros cries out for Shan.