Lucie receives an early morning wake-up call from the hotel receptionist. She didn’t ask for one, but she can guess who was responsible for arranging it. Her beside radio alarm goes off too and she listens to a news broadcast which reveals the date to be 21st October 2015. She calls at the Doctor’s room next door, but there’s no answer. On the radio, a newsreader announces that contact has been lost with Britain’s Terra Nova space probe and comparisons are being made with the apparent disappearance of NASA’s solar probe two days ago. Lucie realises this is where the Doctor will have gone…

At the space tracking station in Buckinghamshire, the Doctor introduces himself to the project head, Dr Avishka Sangakkara, and learns that the man has spent four years of his life and £75 million of tax-payers’ money on the Terra Nova project. It’s too much of a coincidence that both Britain and America have lost track with their probes at the same time and they’re both convinced it’s can’t be down to a technical problem. The Doctor explains that he used to advise UNIT on this sort of thing and offers to help find out what’s really going on.

The Doctor phones Lucie at the hotel and says he doesn’t know how long he’s going to be needed here. She agrees to meet up with him later, but then she’s distracted by none other than Karen Coltrane, her former colleague from Hulbert Logistics. Karen explains that she was fired by the Headhunter three years ago and was unceremoniously dumped back on Earth. It’s a long story, but Lucie has plenty of time to kill…

Dr Sangakkara introduces the Doctor to the rest of his team, including research assistant David Mason. Their probe was following close behind the Messenger Probe, but the British team was hoping to take advantage of a delay and reach Mercury before NASA. The Terra Nova had been due to dive through the exosphere of Mercury in four day’s time with the aim of retrieving water samples from the planet surface. But now both teams have lost all contact with their respective probes.

Karen explains that she was dropped off in London, but she had no home to go back to as her mum had died and her dad was nowhere to be seen. She couldn’t get a job because of the gap on her CV and she ended up living in squats for a while, but then she met some people called the Eightfold Truth who taught her how to work through her problems by changing her attitude to life. They let her work for them in exchange for food and somewhere to stay. She says they’ve given her a whole new purpose in life and she thinks they might be able to help Lucie too. Lucie turns down the offer, but Karen insists that she’d benefit from their help. Then, mysteriously, Karen whispers that something is coming and the Eightfold Truth are the only people prepared for it. Karen says she feels bad about the way she treated Lucie before and she sees this as an opportunity to make amends. Lucie thinks it all sounds a bit weird, but as the nearest centre is only five minutes away, she agrees to go and see what it’s all about.

The Doctor asks if he can borrow a computer and David is surprised when he starts re-creating a programme from memory. He quickly discovers that something has got hold of the Terra Nova probe and is changing all the technology on board. The reason they’ve lost contact is because the probe no longer understands any of the instructions they’ve been sending.

Karen takes Lucie to the nearby Eightfold Truth centre and introduces her to Rob. He tells Lucie they call their introductory session a “review” and they believe in natural therapeutic techniques using energy crystals. All she needs to do is give truthful answers to some very simple questions and if this highlights any problems, they can then help her work them out and bring her psyche back into balance. Lucie doesn’t like the sound of it, but Rob says they can just talk if she’d prefer that. Karen tries to give her an energy crystal which Rob says will clear her mind, reduce confusion and help her to relax, but Lucie refuses. Rob explains that their group believes the world can be a better place and their mission is to help people reach the next stage in human achievement. Lucie suddenly finds the crystal in her hand, although she doesn’t remember picking it up. Rob begins by asking her some questions about her current life which she finds hard to answer directly.

The Doctor finishes the computer programme and explains that it will help the systems down here work more closely with the probe in space. They receive a signal from the probe and strange data starts appearing on their screens. Suddenly the Doctor realises that whoever has got hold of the probe knows what they’re doing. He tries to break contact by shutting everything down.

Without realising it, Lucie has started to reveal small details about her life with the Doctor. Rob appears to be concerned and says it sounds like Lucie is blindly following the Doctor’s agenda without knowing any of the details. Lucie becomes defensive, but Rob says it isn’t easy when someone learns how small they are. He suggests they continue the “review” at their Centre of Balance, which is the Eightfold Truth’s main headquarters. Karen promises they can be back within a couple of hours and although Lucie isn’t sure she’s doing the right thing, she’s finding it increasingly difficult to turn their requests down. Karen tells her she might be lucky and get a chance to talk to their leader, Mr Goodman, who can explain things better. Before long, they arrive at the old BBC Television Centre, which Rob says their group bought three years ago. The building now contains lecture rooms and a large residential block which is home to a whole co-operative community who work for their movement. They have many members all around the world and most of them lead ordinary lives, but this is where their helpers and the people who need their support live.

The Doctor tells the Terra Nova team they’ve been deliberately attacked by whatever it is that’s got their probe. He thinks it’s very likely to be alien and it seems to be trying to use their probe to communicate, but he’s not sure who with. Unfortunately all the optical telescope operators have been reporting difficulties and are unable to get a clear view of that area of space. Dr Sangakkara believes they’ve lost their probe for good, but he says they were still able to retrieve some data which they might find useful. The Doctor offers to get out of their hair and decides to book into a guest house while he tries to puzzle everything out.

Rob takes Lucie to a meeting and introduces her to a group who are here to learn about themselves. She’s surprised to find that she’s still holding the energy crystal and Rob reminds her that they have a very relaxing influence on people. Lucie believes the people here are vulnerable and she objects when Rob tries to draw her into the group, but he assures her he just wants her to become empowered so she can take hold of her own life. He begins by asking her questions about her goals…

The Doctor tries to call Lucie’s mobile, but only gets through to her answer phone. It’s two o’clock in the morning and he apologises for losing track of time. He says he’s still working on the missing probe problem and will try to catch up with her later.

Back at the Centre of Balance, Lucie is in tears. She’s spent the entire night talking to Rob about her life and she’s now totally convinced that the Doctor has been manipulating her all this time. Rob tells her she’s taken an important step towards making herself her own person. He promises her that what they’re doing here will change her whole world…

The Doctor returns to the Terra Nova team feeling relaxed after enjoying nearly a whole hour’s sleep. He tells them he made a breakthrough. He believes the probe didn’t understand the data it was picking up and whatever is out there is still working on re-purposing the probe. He thinks he’s worked out a way of reverse-converting the code so he can work out what the original input was supposed to mean. But first he wants to call Lucie.

At the Centre of Balance, Lucie’s phone rings. She answers and coldly tells him she doesn’t want him involved in her life any more. She tells him there’s stuff in her life she needs to work out on her own and then she hangs up. Karen congratulates her and tells he she’s taken a massive step. Lucie feels a lot better now and Karen tells her that’s what she can expect to experience from now on.

The Doctor is confused by the phone call and adjusts the Terra Nova tracking systems so he can use them to track where Lucie is. He discovers she’s at the BBC Television Centre and Dr Sangakkara tells him that’s where the Eightfold Truth is based.

Rob tells Lucie that as a reward for doing so well last night, he’s going to introduce her to the First Aspect of the Truth. As the name of their group suggests, there are Eight Aspects of the Truth - the First states that humankind must embrace it’s destiny and move towards it. Although everyone will be moving in the same direction, it’s up to each individual to decide for themselves when to take the first step. Lucie is absolutely convinced this all this makes sense. Rob hands her some goggles that he says will read any changes to her brain activity. He has some more questions for her, but she says she doesn’t mind as she likes questions.

Sangakkara tells the Doctor that the Eightfold Truth have had a much higher profile over the last few years, and even more so in recent weeks. Nobody knows what they’re about, but David thinks they’re really weird people. Their aim seems to be to help people achieve their potential, but the Doctor doesn’t think that sounds much like Lucie’s kind of thing. David tells him they’re always on TV and radio, so the Doctor listens in to a programme that’s interviewing Clark Goodman, the founder of the Eightfold Truth, and Kelly Westwood, a journalist who wrote the book “The Octopus Cult” and it’s soon-to-be published sequel “Don’t Believe the Truth”. The programme has already interviewed several former members of the Eightfold Truth, but Goodman dismisses their views and says they have grudges against his group as they were disappointed by their own failures. Goodman and Kelly begin to argue on-air and the journalist reveals that her new book will be the first time anyone outside the group will learn all Eight Aspects of the Truth. She accuses them of ripping off Buddhist ideas and says their so-called energy crystal focus group techniques actually make their members highly suggestible to brainwashing. The interview is brought to an end when they run out of time. Goodman immediately leaves via a side exit, but before Kelly can leave she’s approached by the Doctor who’d raced to the studio. She’s accustomed to people wanting her help because a friend or relative of theirs has joined the cult, so she accepts his invitation to go for a coffee.

Lucie wonders how well she’s done in her “review”, but Rob tells her it’s more to do with finding the right course of action to complement the individual. However, when Lucie’s brain scan comes through, both he and Karen are shocked by what they see. Rob immediately calls Clark Goodman and tells him the subject is a perfect match for the Chosen One. The news has already spread around the group but Goodman says they should have got Mary to check the result first. He promises to return to the Centre soon.

Kelly tells the Doctor that the membership of the Eightfold Truth has increased five times in the past five years. She believes they prey on insecure and frustrated people by telling them what they want to hear. The group was founded back in 1987 by Clark Goodman, a self-help guru. Her view is that he’s built up an army of followers who’ll do anything for him simply as an ego trip. She refuses to tell the Doctor more about the mythology behind the cult as this is the main selling point of her forthcoming book, but she says she hopes to bring the whole group down. The Doctor thanks her and gets up to leave, but as he does so he steals the book from her bag. He says he’ll return it and promises not to reveal any spoilers.

To everyone’s amazement, the TARDIS materialises in the middle of the Terra Nova tracking station. The Doctor apologises and says he’d intended to land outside the building. He asks how the computer is getting on with the reverse-conversion and Sangakkara says it’s slow but he has some fragments of the data ready if he needs to look at them.

Rob tells Lucie that her results show she could be very, very important to them. He tells her Mary Bradbury is in charge of the organisation’s technology and she has to check the results to make sure they haven’t made a mistake. Karen wishes her good luck and says everyone is hoping it’s true. When Lucie meets Mary she thinks she recognises her, but the Headhunter assures her that can’t be right as this is the first time they’ve ever met. Lucy accepts this, then the Headhunter asks Rob and Karen to leave the room so the two of them can talk alone. She orders Lucie to sit on the floor and tells her to relax and empty her mind.

The Doctor examines the data from the probe and finds that it’s worryingly familiar to him. He tells Sangakkara it’s written in the same computer language his own people use to drive their TARDISes. In Kelly’s book, the Eighth Aspect of Eightfold Truth says that within their lifetime, a Rebel Sun will come to Earth and its fire will cleanse the planet of all but the most loyal followers. Sangakkara says it’s gibberish, but the Doctor says the data from the probe is coming from a Stellar Manipulator, which is an artificial Sun. David arrives with a parcel that’s addressed to the Doctor, which is odd as only UNIT and Lucie know he‘s here. The Doctor takes the parcel and immediately orders everyone to evacuate the building. He asks Sangakkara to take the TARDIS key from his pocket and open the door for him. Suspecting it’s a bomb that might go off at any moment, the Doctor heads towards his ship - but then the parcel activates and he’s instantly enveloped in an evil looking gas…

Lucie is getting scared, but the Headhunter persuades her to keep calm. Patiently, the Headhunter waits for someone to arrive…then eventually a small blue light appears on the floor, and inside the light is a huge Spider. The Spider turns to Lucie and introduces herself as her new mistress, then ignoring Lucie’s cries of terror, it scuttles towards her and leaps onto her back…

The Doctor wakes up to find himself in a hospital bed. A nurse tells him he’s been unconscious for 23 days and she laughs when he asks if anything happened while he was asleep…

In the outside world, the general feeling among the public is that they’ve been let down by the politicians and the scientists as none of them have an explanation for what’s happened, nor do they have a solution. Dr Sangakkara has to reassure David that it wasn’t the fault of the Terra Nova team. They hope to be able to return to the tracking station later today if they get the all-clear, but David decides he can’t take the stress any longer and leaves to join up with the Eightfold Truth. Sangakkara gets a call from the hospital and is relieved to learn that the Doctor has woken up.

The latest statistics show that the Eightfold Truth now has 244 million members worldwide and although Goodman should be proud of his achievements, he’s starting to find it a little claustrophobic in the Centre of Balance. He’s hoping to persuade the new recruits to stay in their own homes rather than move here, but Lucie tells him the people feel safer when they’re close to him. She reminds him that soon they’ll have the whole world to spread out in, but he admits that it’s taking him some time to adjust to the fact that his prophecies have come true after all this time.

The Doctor can’t remember anything after his meeting with Kelly, so Dr Sangakkara fills him in on what happened. After hearing an explosion in the tracking station, Sangakkara found the Doctor unconscious on the floor and called an ambulance. The parcel turned out to contain small explosive phials of Polonium-210 and the Doctor suffered serious radiation poisoning. The Doctor admits that the last time this happened, it actually killed him and he reveals to his friend that he’s not human and is able to regenerate at the point of death. Sangakkara isn’t too surprised and says everything seems plausible these days. The Doctor says he realised the greatest danger was breathing the Polonium-210 in, so he closed down his respiratory system and induced a coma so his body could repair the damage. Sangakkara then opens the blinds on the window to show him a huge burning Sun in the sky. The Eightfold Truth are attributing this to what they call the Rebel Sun, but the Doctor realises this is what the probe was picking up before he was attacked. It’s getting closer all the time and it’s expected to reach Earth in a couple of days. People believe it’s a roving star come to judge everyone and that only the followers of the Eightfold Truth will survive, but the Doctor and Sangakkara know it as the Stellar Manipulator, a form of technology devised by the Doctor‘s own people. The Doctor last saw it on the other side of the Universe. It was built to manipulate all forms of stellar energy and as it’s sucking energy from Earth’s Sun, it could easily destroy the world. But who is controlling it..?

Rob nervously approaches Goodman and Lucie and tells them he represents a group of the longer-standing members of the Eightfold Truth who joined before the arrival of the Rebel Sun. They now form a minority and are worried that the membership is growing too fast. Lucie reminds him that their aim is to spread the word and they should be pleased it’s reaching so many people, but Rob is concerned that the entrance procedure has become less thorough and many of the new members aren’t even having “review” sessions. Goodman tells him time is short and they’re committed to saving anyone who is willing to commit themselves to the group, but Rob says the new people didn’t have to demonstrate any loyalty before being allowed to join. Lucie dismisses his concerns and says he and his friends will be recognised and rewarded for the loyalty they’ve shown.

Now that the Eightfold Truth‘s predictions have started to come true, Kelly is interviewed again about her opposition to the organisation. She points out that most of the new recruits don’t appear to share the group’s philosophy at all but have joined up in the hope that they’ll be safe. She wonders what the organisation will do now they have a vast number of followers who don’t actually follow their beliefs. She asks people to stop panicking and look at the situation subjectively.

At the hospital, the Doctor learns that the Terra Nova station is clear of radiation now that the TARDIS has soaked it all up, so he asks Dr Sangakkara to return there and trace any signals being broadcast from Earth in the same computer language that was coming from the probe. He says this will be the controller for the Stellar Manipulator and they should be able to pinpoint it thanks to the modifications he’s made to their systems.

One of the more recent recruits at the Eightfold Truth is David Mason. He’s surprised that they’re so willing to let him join up without asking any questions about his reasons, but they tell him they’re here for anyone who asks for help. With so many new members coming in, they’re limited in how much attention they can devote to each person, so his processing is very swift. However, his scan shows up something interesting and it appears that he feels guilty for what’s happening. Karen tells him there’s no need for him to feel that way and adds that there’s someone here who’d like to talk to him. She calls for Lucie…

The Doctor gets a taxi and heads for Hampstead. The cabbie tells him he thinks the cult is nothing but a group of nutters full of mumbo-jumbo and he suspects alien technology is behind the arrival of the new Sun. The Doctor is relieved to hear this - until the cabbie admits that he’s joined up anyway as it’s better to be safe than sorry.

Lucie meets David and asks him to hold out the crystal he was given when he arrived. She ‘connects’ with him and tells him he’s been worried for some time. He’s been dedicated to his work for many years but has started to believe that the Universe is so vast, there’s no meaning to his life any more. She promises him she can take away the bad feelings and give him something else to believe in.

The Doctor meets up with Kelly and returns the copy of her book. Kelly is despondent that she’d managed to keep the contents of her book secret until it was published - only for the astronomers to spot the Rebel Sun on the very same day. She now believes the Eighth Truth used her to get their prophecy promoted by an independent source just as it was about to come true. If the public had known about the group’s prophecy months ago, everyone would have dismissed them as crackpots, but now they’ve had time to build their power base before they got a rush of converts. The Doctor reveals that he’s not human and tells her the Sun is a piece of technology created by his own people. She suspects he’s feeding her lies in order to discredit her, so he decides to show her some proof. He leaves the room and then seconds later the TARDIS materialises in the room. The Doctor explains that he went down the road, jumped on the Tube, took a train and a taxi to the tracking station, then used the TARDIS to travel back in time and arrive back here before the tea she made for him went cold. She asks if he can use his time machine to go back and sort the problem out before it started, but he says he can’t. She then asks to see President Kennedy’s assassination, but he tells her the world is likely to end in a couple of days and they have more important work to do.

Goodman arranges a meeting with Rob and several of the other long-standing members of the organisation, including Karen. He asks them for their honest opinion about what they think of their Chosen One, Lucie. There’s an uncomfortable silence, then Rob admits that she seems to be influencing the direction of their group quite considerably and they all have reservations about the new members. Lucie has promised them they’ll be rewarded, but Goodman admits he has no idea what she means by that. Although he predicted the arrival of the Chosen One, he hadn’t really expected it to happen until after he‘d gone. It doesn’t feel right to him and he’s even starting to wonder whether he interpreted Lucie’s scan results properly. The others agree and he asks them to reassure people that it isn’t disloyal for them to have doubts about Lucie.

The Doctor wonders how the Sun will be able to distinguish those people who aren’t part of the group before it destroys them. Kelly tells him all members are given meditation crystals, but she doesn’t have one to show him as their owners are holding onto them for dear life or are selling them on eBay for tens of thousands of pounds. When she reveals that she’s due to be interviewed on TV twice more today, the Doctor has idea what she should say…

The Headhunter is irritated when Lucie enters her office without knocking, but Lucie reminds her they should have no secrets in the Centre. As the Headhunter predicted, there’s been some unrest growing among the longer-standing members of the group, but Lucie says this may work in their favour as it means they’ll be too preoccupied to notice what else is going on. The Headhunter tells her the journalist Kelly is still stirring up trouble, but Lucie is confident people will be too frightened to pay any attention to her. Karen arrives and warns Lucie that Goodman is spreading rumours that he may have got the prophecy about the Chosen One wrong. Once Karen is dismissed, Lucie decides to advance their plan so their most loyal members get their reward earlier than expected. She wonders if Karen would be so willing to help them if she knew what was really going to happen. Personally, the Headhunter has no concerns about the fate of the human race, but she admits that she only agreed to work with her new allies as her own people have evolved natural defences against other races with psychic powers. Lucie interprets this as a threat, but the Headhunter assures her it was just a friendly warning.

The TARDIS materialises back at the tracking station where Sangakkara has just finished re-rigging the systems as the Doctor suggested. The work has been slow because all his staff have left, probably to spend whatever time is remaining to them with their families. The Doctor makes some final readjustments and then rushes over to watch Kelly’s interview on TV. As promised, she produces some computer data that she says was coming from inside the Rebel Sun, which proves it’s being controlled deliberately. At the Centre of Balance, Lucie and the Headhunter are also watching the interview, but they believe it’s too late for anyone to stop them.

The Doctor has connected the TARDIS to the tracking station systems to speed the process. He and Sangakkara check the results and immediately identify hundreds of signals being beamed out into space and all coming from the London area. The Doctor suspects that only one of those sources can be genuine and the others are all red herrings. He’s going to have to filter them out, but he knows they don’t have time for that. The next morning, the TARDIS lands back at Kelly’s house and the Doctor wakes her up. She’s exhausted after doing so many TV and radio interviews and is far from impressed when he presents her with a gadget that looks suspiciously like it’s been cobbled together. He tells her it’s a triangulation device that will contact the Stellar Manipulator and force it to respond. It won’t give them control over it, but the effects will still be dramatic and it’ll prove that the Sun is just a piece of technology after all and that it doesn’t have a will of its own.

During her earlier interviews, Kelly had publicly proclaimed that she’d be able to turn the new Sun green at midday to prove that it‘s not real. The Headhunter is worried and consults with Lucie. It’s 11.48am now and their followers are starting to mass in the main hall, demanding to see their Chosen One. Lucie agrees to go down and hear what they have to say.

Kelly has organised the TV cameras of the world to watch as she activates the device. She’s about to begin a countdown, but then - just to prove she has complete control over the Sun and can change its colour whenever she chooses - she presses the button straight away. A signal pulses out from the device…

Lucie is confronted by a hostile group led by Goodman. He tells not everyone has full confidence in the changes she‘s introduced recently and he’s concerned that they’re losing sight of their original purpose. Lucie reminds him they were supposed to be helping people and that’s exactly what she’s doing. Before they can discuss the matter further, Rob races into the hall in a state of distress and tells everyone to look up at the Sun outside…

The entire sky has turned green, just as Kelly predicted it would. She assures everyone there’s nothing to worry about and says it happened as a response of the signal she sent. She says this demonstrates that the Sun is an artificial object that responds to outside stimulus. Unfortunately, the effect it has on the crowd is not the one she was expecting. Instead, people start to scream and panic…

The group outside the Centre of Balance turn to Goodman for answers, insisting that he should know what’s going on as he foretold it. The old man seems frightened and confused, so Lucie steps in and tells them it’s a sign that the next phase is due. She turns to the crowd and tells them that those people who were members before the Sun arrived should go back to the main hall and concentrate on their crystals as their reward is at hand.

Kelly returns home and finds the Doctor already there, watching her earlier press conference on the TV. He was also surprised by the reaction of the crowd, but Kelly realises they were too scared to listen to her explanation. The Doctor becomes angry and despondent. He accuses people of being stupid and wishes he was back on his adopted home world, Orbis, but it’s been destroyed. He remembers it was Lucie who came and rescued him and Kelly reminds him that he owes her a great debt. The only good news is that one of Kelly’s old contacts has given her his crystal after deciding he didn’t want anything more to do with the Eightfold Truth. The Doctor is overjoyed and says this changes everything. Unfortunately when he examines the crystal, he realises things are even worse than he thought. It’s one of the crystals from Metebelis Three…

Goodman demands to know what their reward is. Lucie tells him their oldest followers will be of great importance to the new world they’re building. She plans that they will reach out into the Universe as far as they can go and spread their faith. Unfortunately Goodman himself is no longer of any use to her as he’s revealed himself to be a cynical, exploitative wretch. They hear screaming coming from nearby and Lucie follows Goodman as he rushes into the hall to see what’s going on. He’s horrified to see everyone is being attacked by giant spiders. Lucie rebukes him for using a forbidden word. More spiders appear from nowhere and Lucie tells him this had always been planned. The followers of the Eightfold Truth now belong to the Eight Legs!

Lucie reveals to a shocked Goodman that his philosophies and techniques were all implanted in his brain by the Spiders years ago, together with the means to draw people in. Now that his recruits have become malleable and suggestible, the Spiders will find it easy to take over their bodies. Knowing they have no further use for him, Goodman realises they plan to kill him. He rushes through the screaming crowd, urging everyone to escape, and Lucie orders her followers to chase after him…

Karen returns to the Headhunter, concerned that things are getting a bit manic in the hall. She sees another Spider waiting in the office and realises it’s here to take her over too. She protests that this was never part of the deal, but the Headhunter tells her it was, it’s just that she never told Karen about it. Ignoring Karen’s screams, the Spider leaps onto her back and instantly takes over her body. The Spider is disappointed that the body she’s been allocated is so short, but the Headhunter assures her it’s considered very attractive in this era of Earth’s history.

The Doctor tells Kelly about the crystals from Metebelis Three, the famous blue planet of the Acteon Galaxy. He says it’s very rare to find one as perfectly formed as the one she was given, but Kelly reminds him that the Eightfold Truth have millions of them and are giving them out to every member. The Doctor suspects someone’s found a way to manufacture them. The crystals can concentrate and amplify thought and although they’re very powerful teaching tools, they can also do a lot of damage in the wrong hands.

Goodman calls out to the members, pleading with them to follow his orders one last time. Close behind him, some of the Spider-controlled recruits open fire with blasts of blue energy from their hands. He manages to avoid being hit and eventually escapes through the main door. Speaking with the voice of a Spider, Rob tells the terrified crowd that Goodman is no longer their leader and they shouldn‘t believe his lies. He says they’re not here to kill them, but to save them…

The Doctor calls Dr Sangakkara at the tracking station and learns that he’s managed to narrow the search for the signal down to about half a dozen possible locations in the London area. Just then Sangakkara sees a news report on the TV and he turns the sound up so the Doctor can hear it. They listen as Lucie announces that their former leader Clark Goodman has stepped down from his position, but the Eightfold Truth still welcome new members into their group.

At Kelly’s house, the Doctor explains that Lucie must have been taken over and reveals that intelligent mutant Spiders are behind everything. He tells Kelly the story of how the Spiders first arrived on Metebelis Three and how they were transformed by the power of the crystals. Their psychic powers became considerable, making them one of the most advanced races around. He thought they’d been destroyed, but it seems he’s always making that mistake. There’s a knock at the door and Kelly opens it to reveal a dishevelled and shocked Goodman, who pleads for their help.

Lucie gives instructions for her broadcast to be played twice more before the ’main event’ as it’s important people understand Goodman no longer has any authority over their group. She suddenly feels very tired and decides to get some rest. Once she’s gone, the Spiders inhabiting the bodies of Karen and Rob agree that they don’t know who to trust these days. Now that the Spider inhabiting Lucie is resting, it’ll be the ideal time for them to get away…

On the way to her room, Lucie encounters David and tells him that when the moment comes, she’d like him to be at her side so he can be the cornerstone of the new world they‘re building. He notices there’s something odd about her voice, but she tells him not to worry and that he can expect to see and hear a lot of strange things in the next few hours. Then she makes her excuses and heads back to her room.

Goodman admits that he knew Kelly’s address because he’d had her followed a long time ago. In his state of panic, he couldn’t think of anywhere else to go and he hoped she’d help him if he told her the truth. He reveals to Kelly and the Doctor that he made the whole thing up and the entire mythology about the Eightfold Truth, including the Rebel Sun and the Chosen One, was faked. Although he’d enjoyed the power it gave him, he claims that the real reason he did it was because it made people happy and gave them something to work towards. However, while he was encouraging people to maximise their potential, he didn’t want to create conflict amongst the group so he deliberately came up with a prophecy that could be endlessly deferred. The Doctor refuses to let him justify what he’s been doing and accuses Goodman of brainwashing people, but the man is in shock now that everything he predicted is starting to come true.

The Doctor asks him where he got the crystals and Goodman says he found one on a pot-holing trip in Yorkshire. He took it home and that was when the whole idea about the movement started. He soon realised that when he concentrated on the crystal he was able to make other people believe him. He set up the Eightfold Truth and sent out expeditions to find more crystals. The Doctor reveals that the Spiders have been manipulating him from the beginning by planting thoughts in his brain. Kelly reminds Goodman that there are subtle references within the text of the Eight Aspects of Truth that confirm the Doctor’s theory, including a parable about spiders building webs, which he used as an inspiration to the others about building a better world. The Spiders evidently set up the entire thing, knowing the prophecies would come true.

Goodman says he added a reference to the Chosen One as a way of anointing his successor if he ever wanted to stand down, but then suddenly people actually started claiming she’d arrived. He tells them that a few years ago he brought in a new technical specialist who equipped the group with systems for scanning brain activity for psychological profiling. It was intended to be a way to encourage his followers to find new recruits, but then they found Lucie. The Doctor says he’d like to think that Lucie took over running the organisation simply to bring it down from the inside, but sadly he thinks it’s more likely she’s been possessed. Goodman says that before he left he saw the Spiders attacking people and jumping onto their backs. Kelly says they’re aliens who intend to take over the world, but the Doctor is worried it might be even worse than that…

Inside her mind, Lucie finds that the grip of the Queen Spider starts to loosen as it rests. She begins to taunt the Queen, pointing out how hard it must be to keep her locked up in a corner of her own brain and out of harm’s way. Lucie accuses the Spider of hiding away, afraid of showing even a moment’s weakness in front of their human minions. She even suspects the Queen might be going schizophrenic and warns that she has no intention of giving up control of her body without a fight, but the Queen says she can still crush Lucie if she wants to.

As the Spiders controlling Karen and Rob leave the Centre of Balance, they find themselves confronted by a mob of people who believe it’s the end of the world and are keen to “have some fun” before they all die. Not wanting to waste any more time, the two possessed humans raise their arms and wipe them all out with a blast of energy.

Dr Sangakkara calls the Doctor and tells him he’s found the control point at the old Olympic Village. He emails Kelly the exact location and the Doctor thanks him for saving the world. He asks Sangakkara to keep watching and to contact them again if there are any significant changes.

Karen and Rob confront the Spiders guarding the control system for the Stellar Manipulator and announce that they’re taking over the operation as they no longer believe the Queen is fit for command. The Spiders protest, declaring their loyalty to the Queen, so Karen and Rob destroy them with further blasts of energy.

Lucie wonders why the Queen chose her body rather than someone who’s been part of the movement for years and whose personality had already been totally dissolved, especially as taking her over was only going to attract the Doctor’s attention. The Queen believes they have already dealt with the Doctor, but Lucie laughs and decides to rummage around inside her own head to see what she can find. The Queen orders her to stop, but Lucie refuses and challenges the Spider to do her worst…

The Doctor, Kelly and Goodman arrive at the location Sangakkara gave them and Goodman reveals that the apartment block is being used by his organisation as a residential overspill. He knows Lucie had sent a couple of their longer-standing members here, but he doesn’t know why. The Doctor believes they’re here to protect the controller of the Stellar Manipulator, but he has a plan to take it from them. He hands each of them some stones taken from the planet of the Spiders which are the natural opposites of the blue crystals and will help dissipate their energy. The Doctor warns Goodman not to use this opportunity to get revenge, but Goodman insists that revenge is the only reason he’s helping, whether the Doctor likes it or not. Suddenly an energy blast explodes next to them, taking the roof clean off a nearby car. They take cover behind a wall, but as they have no choice but to stick to their agreed plan, Goodman races off towards the nearest entrance.

Karen and Rob watch in amazement as Goodman calls out to them. Thinking they might be able to use him to disrupt the Queen’s authority, they explain to him that they’re taking over and that he’s welcome to join them if he wants. As they invite him inside, the Doctor and Kelly move around the back of the building towards another entrance. They know they can’t trust Goodman, but all they need him to do is cause a distraction. However, another explosion nearby tells them they were expected after all. Rob tells them to surrender, but the Doctor and Kelly hold up their stones for protection and rush forward. The other Spider-possessed humans concentrate their energy and open fire, but it’s too late and they’re knocked unconscious. The Doctor and Kelly rush upstairs…

The Headhunter interrupts the Queen’s rest with news that some people are attempting to gain access to the controller - and one of them is the Doctor. The Queen is horrified to learn that he’s still alive, but she’s confident he won’t have time to do any harm and orders the Headhunter to leave her alone. The Headhunter reminds her that the point of arrival is due in less than 15 minutes and their followers around the world will be expecting to see her when it happens. The Queen suggests they play a recording as she can’t be distracted from her real work, then she asks for David to be sent up to her. Once they’re alone again, Lucie taunts the Queen, knowing that it took all the Spider’s energy just to keep her at bay for a few moments. Lucie realises they have the Stellar Manipulator control device, but the Queen says the information has come too late to be of any help.

Goodman makes his way to the room where Karen and Rob are guarding the control device. They tell him the Queen is an old fool who plans to hide inside humans forever so they can manipulate the cosmos unseen, whereas they want to revel in the devotion of every being they come into contact with. While Kelly stays outside to fend off the other Spider-possessed humans, the Doctor enters and persuades Karen and Rob to stare into the blue crystal that Kelly gave him. Before long a huge Spider fall off Karen’s back and disappears. Rob warns them they won’t find him so easy to defeat, so the Doctor calls upon the support of Goodman and Karen. Eventually they succeed and Rob’s Spider also leaps from his back and disappears. The Doctor explains that the Spiders have the ability to travel across the astral plane, but they need a human host when they arrive at the other end. Unable to find a new host, they’ll have returned to their home planet.

Rob is overcome with shock and has to sit down. Goodman pleads with the Doctor to set free the hundreds of other people who’ve been possessed by Spiders, but they can hardly rescue them one at a time. While the Doctor tries to crack the isomorphic controls of the device, Karen admits that she was never a true follower of the Eightfold Truth. She knew about the Spiders all along and she and the Headhunter were responsible for placing the crystals at the pot-hole in Yorkshire where Goodman could find them, but it was never part of the plan that she would be possessed too. Kelly joins the group as Goodman switches on a radio and they listen to Lucie, urging her followers around the world to be positive. She bids farewell to those people who’ve decided not to join them and says she’s sorry she won’t be seeing them on the other side.

David is shocked when Lucie starts to speak to him with two different voices - her own natural voice and that of the Queen Spider. The Queen apologises for her erratic behaviour and says it’s due to the momentousness of the occasion. The Queen tells him to put down his crystal - and then suddenly Lucie grabs it…

The Doctor succeeds in breaking through the device’s isomorphic control, but it still won’t work. He realises the Stellar Manipulator is being controlled from somewhere else and the device he‘s been working on is just a dummy. On the radio they hear an announcement that the Rebel Sun will make its judgement in 20 seconds…

Lucie has realised that the Queen Spider hacked the control device and keyed it to Lucie’s own DNA so that the Sun would home in on her. The Queen’s plan was to take over Lucie and control the Manipulator through her body - but Lucie is confident she’s gained the upper hand and believes the power is now hers. The Queen reveals that Lucie still needs a password and there isn’t time for her to wrest it from her. She congratulates Lucie for fighting well, but it was to no avail. This is the end and the countdown reaches zero…

The people of Earth scream in terror and the Doctor realises they’re too late. The device has activated and the energy of the Rebel Sun is starting to flow outwards. Rob goes into some sort of trance and the crystal he’s holding starts to glow brighter. He mutters praise to the Great One and Kelly says she can hear the same chant coming from the hundreds of millions of people across the world who own crystals. The Spiders are focusing the energy through them via a psychic pulse to create the most powerful hive mind in the Universe.

David can hear the psychic pulse spreading across the world and although it starts to hurt him, the Queen tells him not to fight it as it’s the sound of the ‘new truth’ that will unite thousands of planets in praise of her. Eventually he succumbs to its influence and the pulse begins to dissipate.

Lucie finds herself in an empty white void. She calls out, but there’s no reply. She stumbles across a tiny spaceship that’s far too small to carry anyone and notices that it has a Union Jack flag on it.

The Doctor and the others recover after having been knocked unconscious by the effect of the psychic pulse. Goodman and Karen both experienced a vision and now suddenly everything seems to make sense to them, as if a light had been switched on inside their heads. The Doctor asks them about the Spiders, but when Karen tells him the Eight-Legs don’t accept that name, he realises something has gone wrong…

When David wakes up, he tells the Queen that the Eight-Legs mean everything to him and he now knows she is the greatest of them all. He asks if he can see her in her true form and she says she may allow that one day.

Goodman and Karen are in a state of euphoria, believing the Eight-Legs want them to be happy and in return all they ask for is their loyalty. The Doctor tries to convince them they’ve been brainwashed and that the psychic pulse has seeded these thoughts in their minds, but they refuse to listen. They both pity him and believe he has an empty life with no hope of salvation. When they prepare to put him out of his misery, the Doctor whips out the blue crystal again and tells them to examine what they know about the Spiders. Slowly, they both start to realise what’s happened and they fight to purge the Spiders’ thoughts. In a flash, Goodman and Karen are restored to normal. They remember believing that the Spiders were gods. The Doctor explains that the possessed humans are absorbing energy from the Stellar Manipulator through the blue crystals to boost their power as a hive mind, but eventually it will burn out their brains just as it did to the Great One on Metebelis Three. Goodman and Karen ask about the other people - including Kelly - but the Doctor is exhausted after bringing the two of them back to their senses and he doesn’t have the mental energy to de-programme everyone. In any case, he can’t go around rescuing everyone individually, so they need to find a large scale solution.

At the tracking station, Dr Sangakkara is surprised when Lucie’s face suddenly appears on the monitor screen which is broadcasting a direct feed back from their missing space probe. He recognises her from her recent TV appearances and asks her where she is, but she doesn’t know and says she found herself in an area of white nothing. He adjusts the angle of the on-board camera to check here surroundings and proclaims that the Eight-Legs have given then a glimpse of Heaven!

The Doctor says the Spiders will be busy maintaining the pulse, but if they’re confronted, they’ll draw on the power of the Stellar Manipulator to boost their energy attacks, making their defensive stones useless. They head for the nearby car which was damaged by the Spider attack when they first arrived and the Doctor asks Goodman to drive while he rests. Before they can climb inside, Kelly joins them and says she’s been ordered to destroy them. The Doctor, Goodman and Karen dive for cover as Kelly raises a gun and starts shooting at them. Although the vehicle is badly damaged, Goodman manages to drive off with the Doctor and Karen in the back. Kelly leaps in front of the car and is knocked to the ground. The Doctor gets out and checks on their former ally, but Kelly is only able to mumble about “something happening” before she dies. Her body starts to glow and then a ball of energy shoots up from her dead body towards the Rebel Sun in the sky. The Doctor says they don’t have time to do anything with Kelly’s body, so they leave it where it is and drive away.

The Headhunter calls on the Queen and reports that the psychic pulse will probably cover at least 50 light-years before it burns out and it’ll continue to spread out even after that point. The Queen says she intends to use the hive mind once again as the attempt to seize control of the Manipulator has convinced her that her own people cannot be trusted.

The Doctor asks Goodman to drive them to Kelly’s house where they can pick up the TARDIS and go on to the tracking station. He asks Karen what she knows about the Headhunter’s deal with the Spiders and she tells him they needed to bring the Stellar Manipulator half way across the Universe, but that would have taken too long. As any attempt to transmat it would take more power than they had, the Headhunter travelled to Orbis and stole the manipulator control, tricking the Doctor into thinking she’d thrown it into the sea. She’d already taken a sample of Lucie’s DNA and used it to programme the Manipulator to follow Lucie. It got caught in the TARDIS‘s wake and has been following them through the Vortex ever since. Karen thought the plan was just to hand over the members of the Eightfold Truth and she had no idea the Spiders intended to take over everyone on the planet. The Doctor is far from impressed and criticises Karen for getting involved in the Headhunter’s plan, but she argues that anyone who was stupid enough to go along with Goodman‘s organisation deserves all they get. They pull into a drive-in and the Doctor orders food for each of them, but the cashier recognises them as sworn enemies of the Eight-Legs and they have to make a hasty getaway.

Kelly Westwood wakes up and finds herself in an empty white void. She’s greeted by Lucie, who recognises her from her TV appearances. Kelly doesn’t know how she got here and the last thing she remembers is being hit by a car, so she assumes the Eight-Legs have rewarded her loyalty by sending her to Heaven. Lucie assures her the Spiders are not in charge of who goes to Heaven, but then they’re joined by a strange alien who also tells them he was also brought here because of his devotion to the Eight-Legs.

The TARDIS materialises back in the tracking station and the Doctor races out, keen to discover whether Dr Sangakkara has escaped from the influence of the Spiders. Unfortunately his friend turns on him angrily and accuses him of being an enemy of the Eight-Legs. While Goodman and Karen spread out to check on the other staff members, the Doctor uses the blue crystal to purge Sangakkara of the Spiders’ influence. Within seconds, the man is restored to normal and the Doctor asks him whether they’ve been picking up any unusual emissions heading into the Stellar Manipulator. Sangakkara tells him they haven’t, but they have restored contact with their space probe.

Before long, the white void is full of displaced followers of the Eightfold Truth. They come from all sorts of races and from worlds far, far away, including at least one member of the Trell. Lucie is disturbed that things are happening so fast, but Kelly warns her that if she won’t open up her eyes to the truth, she’ll have to talk to the others to see what they’re going to do with her. Determined to find a way out of here, Lucie heads back to the space probe.

Goodman and Karen return and confirm that there’s no one else in the tracking station. Sangakkara is disturbed to see Goodman, but the Doctor assures him that ironically he’s one of the few people now who don’t believe the Spiders are gods. Lucie’s face appears on the screen and she shouts out to the Doctor. She explains that she’d been taken over by the Queen, but she’s alright now although she appears to have been transported to Spider Heaven. More and more people are arriving all the time, all claiming to have died in support of the Spiders. The Doctor realises the Queen must have created a virtual space inside the Stellar Manipulator where she can maintain a connection to all her believers, wherever they are. While Lucie was sharing a brain with the Queen she got to see a lot of her plan and says this is the Queen’s escape route where she could upload her own mind in case the other Spiders overthrow her. Lucie had discovered an emergency exit and used it to come here when the Queen tried to kill her, but she can‘t find a way out and she could really do with one because the other people here are becoming hostile to her. She says the Queen wants everyone to worship her - and although they don‘t realise it yet, this includes the other Spiders. She plans to turn the hive mind against them using the power of the Stellar Manipulator. This will be a good time to mount any attack as she‘ll be at her most distracted. The Doctor thinks Lucie is their best weapon against the Queen as the link between them is a vulnerable spot. Lucie asks if this means that in the real world she’s actually dead, but the Doctor makes an excuse to avoid the question…

When the Doctor returns to the TARDIS, his friends are worried that he’s thinking of leaving them. Instead, he emerges with a cable and tells them he’s going to download Lucie into his ship. The Queen has stolen her body and she only exists as data inside the Stellar Manipulator, but the TARDIS systems are more than sophisticated enough to contain a living consciousness too. He calls out to Lucie, who doesn’t like the sound of what he’s planning. The Doctor sends a programme up to the space probe which will seek out living data and send it down to Earth. He sets the range to make sure it doesn’t also capture anyone standing near Lucie, but it’s impossible to be precise given the level of technology available to him.

Kelly returns to Lucie and tells her the group has decided she can’t stay with them. Lucie offers to repent, but Kelly says they’d need to be sure she was sincere. The Doctor calls through to say they’re ready and then he switches the programme on. There’s a zap of light and Lucie disappears. The Doctor goes inside the TARDIS to see if it’s worked and is delighted when her voice calls out to him from within the ship’s circuits. The next job for the Doctor is to save the world, and for this he’s going to need Karen’s help.

Karen and Goodman return to the Centre of Balance at the old BBC Television Centre and ring the Doctor to tell him they’ve arrived. He says his device is nearly ready and he asks them to call again when the time is right and let it ring once. Karen is worried they might just be killed on sight and she can’t help but think they’re being set up. Goodman agrees, but says they helped to create the situation and he at least has no desire to live in this new world. They approach the main gate and a guard demands to know why Goodman has returned. He tells the guard he’s come to inform them of a plot that threatens them all…

Inside the TARDIS’s telepathic circuits, Lucie starts to laugh at something the TARDIS is thinking about. The Doctor tells her she won’t have to wait much longer as the Queen is bound to make a move soon. Sangakkara enters the ship and is amazed by the size of the interior. He tells the Doctor he’s been watching television and it seems even the greatest thinkers and artists in the world are devoting their work to the Spiders.

The Spiders are sceptical about Goodman’s story and refuse to believe the Queen is trying to wrest control of the hive mind from them. Karen reminds them that the Queen designed the hive mind and Goodman adds that she has past form for this sort of thing. Just as the Spiders decide to confront their leader with the accusation, the Queen herself arrives and demands to know what they’re talking about. Goodman nervously repeats his claim that she’s planning to take over and the Queen responds instantly by shooting him down with a blast of energy. She then demands that the other Spiders apologise to her for giving the accusation credence and for trying to undermine her authority by sowing seeds of doubt in the minds of her loyal followers. She becomes increasingly paranoid and threatens to turn the hive mind against them all…

The phone in the tracking station rings once and Sangakkara tells the Doctor they’ve received the signal from Karen. He wishes the Doctor luck and watches as the TARDIS dematerialises…

The Spiders plead with the Queen for mercy and try to assure her they had no thoughts of betraying her. The Queen refuses to listen and says sharing power is not in their race’s nature and she intends to rule alone forever. David rushes in to see what’s happening and Karen urges him to get out quickly as his ‘gods’ are starting to fight amongst themselves. The Headhunter arrives and regards the Spiders with contempt. Karen asks her why she ever agreed to help them and the Headhunter says she was guaranteed immunity from being co-opted into their new religion, plus enough mineral wealth to set up business in another galaxy. She offers Karen the chance to go with her, but after everything that’s happened, Karen refuses. Suddenly the TARDIS materialises in the hall and the Queen angrily demands that the Doctor comes out and faces her. He emerges carrying the blue crystal, rigged up to TARDIS databanks with the directional control fitted. He calls it his Psychic Implanter and says it can send data directly into a subject’s brain. He shoots the Queen and in an instant, Lucie finds herself back in possession of her own body. The Queen bellows in anger, but Lucie is able to exert her authority over the creature and eventually the huge Spider drops from her back. Determined to find a new host body quickly, the Queen turns her attention to the horrified Headhunter and possesses her.

The Doctor points out that he’s already cut the Queen’s links to the Stellar Manipulator and hive mind, so her whole plan is falling apart. The Queen reminds him that she still has trillions of followers all over the Universe and promises to bring him under her control too. Then she realises something is wrong. The Headhunter takes control again and reminds the Queen that she’d warned her this would happen. Unable to throw the Spider off, she instead places the Queen inside a dormant part of her mind and seals her in. The Doctor is convinced the Queen will break out eventually and the Headhunter can feel the creature attempting to rip her mind to pieces. The Doctor advises her not to resist, but the Headhunter has a better idea. She starts to chant praise to the Great One in order to reflect the Queen’s message back on herself. The Doctor is amazed by his rival’s power and at first it seems to be successful. Worshipping herself has caused a contradiction, resulting in the Headhunter being in awe of herself. However, she’s unable to take the pressure and becomes paralysed. The Doctor needs to help the Headhunter reassert her identity and shake the Queen off. Unfortunately nobody knows her real name as she only ever went by aliases. The Doctor calls to the Headhunter to reveal her name, but it’s too late and the woman’s body completely shuts down. It’s not clear whether she was physically unable to speak or whether she simply refused to reveal herself to him, but regardless of that, the Doctor praises her for being brilliant and courageous. Lucie is still at the centre of the Queen’s web, so the Doctor asks her to open up a path to the Stellar Manipulator. She concentrates and locates the pathway, then takes hold of the Doctor’s hand…

The Doctor miraculously appears before Kelly in the white void. He tells her he’s not really here and has just sent his consciousness through via the Queen Spider’s psychic pathway. He looks around and sees people of various races milling around in confusion now that they’re starting to realise they’re not in Heaven. The Doctor reveals that the Queen is dead and although she sent them to this computer-generated afterlife, she no longer has any control over them. Unfortunately Kelly really did die and the Doctor doesn’t have any way of answering her inevitable questions. However, knowing she was a long-time sceptic of the original plan, he asks if she’d like to help him make the people here stop believing the Spiders are their gods. The Doctor calls Lucie, who’s still at the centre of the Queen’s psychic web, and asks her to let them into the hive mind. The Doctor and Kelly find themselves literally inside the minds of the millions of followers. The Doctor realises these people are afraid and are living in chaos, but now he has an opportunity of keeping them informed. He tells Kelly they need to introduce a new chant for the people to follow - one that tells them to forget the Eight-Legs. They both begin chanting the words over and over again…

The Doctor returns to the real world and Karen tells him all the Spiders have started to drop off people’s backs and vanish. He tells them his plan worked and the Spiders are going home across the astral plane. By telling people to forget about everything that‘s happened, it’s given the creatures a dose of humility and hopefully they won’t be bothering anyone again anytime soon. The Doctor wonders whether there’s anything he can do to erase all the news coverage too… Karen decides to leave and is surprised the Doctor doesn’t try to stop her. Instead, he promises to check up on her one day and hopes she can show him that away from the Headhunter’s influence she’s actually a decent person.

People across the planet are confused, but nobody apart from the Doctor, Lucie, Karen and Dr Sangakkara knows exactly what happened. As a way of saying thank you, the Doctor hands Sangakkara a hard-drive containing the data from Mercury that his probe would have found had it got there. Sangakkara can tell everyone the mission was a success and they’ll believe him, which will make it easier to get the funding for his next project.

The Doctor and Lucie leave in the TARDIS and confirm that the Stellar Manipulator is following them away from Earth. The Doctor can’t destroy it because of the people living inside it, but he can hide it in some obscure corner of the cosmos. Without the influence of the Queen Spider, the neuro-pathways in Lucie’s brain will be starting to close down so she won’t be linked to it any more. The Doctor asks her how it felt to have such incredible psychic powers and she says it was cool, but she didn’t feel like herself. The Doctor suggests they have a break and go somewhere completely trivial, and Lucie knows just the place - Christmas in Blackpool.