As the lift doors at the Savoy Hotel start to close, an American military officer calls out to the Doctor and asks to join him. The Doctor doesn't recognise the man, but the officer claims to know him very well, at least by reputation. The Doctor has been looking for the tearoom, so the military man invites him to join him at the table by the window. He introduces himself as General Tillington -- or 'Stubbs' to his friends -- and explains that he's hopped over to England to hook up with his nephew, who'd be thrilled to meet the Doctor, as he loves time travel gadgetry. To the Doctor's confusion and astonishment, Tillington openly reveals that he knows about the TARDIS and that his scientists would love to get their hands on it. He points to some structures, like cranes, on either side of the Thames, and says they're part of a laser defence system called Global Warning. They can hit any unauthorised object flying in with fifty gigawatts of power. The Doctor demands that Tillington explain how he gained access to time technology, and the General admits that it's still early days and they don't have anything that would match the communications project Nyssa is working on. The Doctor angrily accuses him of spying on the TARDIS, which makes Tillington laugh; his organisation spends billions a year on intelligence, so he ought to get something for his money. The Doctor thanks the General for the scones and makes an excuse to leave, but as he rises from the table he starts to feel woozy. He collapses to the floor and the General assures the concerned onlookers that it must have been something he ate...
Nyssa is hearing voices again. She activates her pocket interocitor -- a sort of temporal communicator -- but she's already starting to hate the thing, even though it was her own idea. She might as well be talking to herself as she's getting no response whatsoever from the Doctor. However, it's possible he may be recording her message, so she continues her report anyway. This is the second day of her one-woman expedition to Rhodes during the Crusades of the 13th century. She's already established that the voices get stronger the closer she gets to the castle, so this afternoon she's planning to sneak in there to see if she can get some answers.
The Doctor wakes up and realises he's been kidnapped, although General Tillington assures him he's merely been 'relocated'. The General feigns outrage that the Doctor's been handcuffed to a chair, but the sergeant claims that it's for his own protection and is standard procedure when someone is under the influence of a consciousness suppressor. The Doctor is released and learns that he's inside a classified facility where time technology is being worked on. He recognises a holographic display, but the imaging is very blurred and he's told that only the really big events show up clearly. Tillington orders his team to re-run the last iteration, and the Doctor is shocked to see an image of the Daleks claiming to be the masters of Earth. The Doctor asks the General what year this is, and Tillington is surprised as he assumed the Doctor would already know. The year is 2158, which means the Daleks should have invaded last year!
It's dark when Nyssa approaches the castle. She tries to contact the Doctor again using the interocitor, but as usual there's no reply. She's picked up some time distortion traces, which have led her up onto a parapet. The Knights below her are starting to get drunk and fight each other now that they've got no one else to battle with. Even though she engineered the interocitor herself, the Doctor assured her it would work, so she can't understand why she's not able to talk to him across the space-time continuum.
Earth shouldn't officially have access to time technology yet, so the Doctor wonders how Tillington's equipment works. The General tells him this is what they call a pre-construction created by their TLTs (Time-Line Technicians), a hand-picked team of trained 'intuitives', or time-sensitives, who can interpret future events here in the Shaping Chamber and transform them into 3-D images. They became aware of the Doctor and his TARDIS from the images they picked up of the Daleks invading Earth, and they witnessed him dropping off his friend Nyssa and heading here. They even saw his interocitor, the actinoidal communications device that he and Nyssa built, so the Doctor realises the images must have been much more detailed than the ones he can see now. The sergeant explains that they were vivid and clear because they were concurrent with the current timeline, unlike the images from the future Dalek invasion, which are blurred and out of phase.
Up on the parapet, Nyssa is about to give up on the interocitor when she's approached by a knight in armour who introduces himself as Mulberry. He's curious about the device she's holding, but Nyssa dismisses it as a piece of worthless junk. He orders her to hand it over as all treasures in the castle have become the property of the Knights of Templar, but she refuses and tries to flee. As he moves to follow her, she warns him that they'll hit the courtyard below should they both fall.
General Tillington shows the Doctor into his office and asks where his time ship is. The Doctor refuses to answer and flippantly asks why their time-sensitives haven't spotted it themselves. The General warns him that his attitude isn't going to help, but then says they need the Doctor's help. Their pre-constructions show that he was instrumental in defeating the Daleks in the alternative version of the present, so they already know that he's on their side, but the General also knows the Doctor well enough to realise that he won't consider this new timeline to be "right". At this precise moment in time, Earth should be a defeated, occupied planet, enslaved by the Daleks. As a sort of payment for landing on Earth's sovereign territory, Tillington wants the Doctor to help them make sure the Dalek invasion never takes place. The Doctor argues that the invasion already hasn't happened (even though he has no idea why), but that's not good enough for the General. His TLTs are detecting a lot of upheaval in time and some of them are getting overwrought and even collapsing with the strain. It's clear there's trouble coming and Tillington suspects it's another Dalek invasion. The Doctor sympathises, but suddenly Tillington confronts him with a toy Dalek and tells him thousands of similar toys have been sold. He's sure there's been no security leak, which begs the question: how do the manufacturers know about the Daleks? And even if there has been a breach, why would anyone start making toys in that image?
The Doctor theorises that the 'idea' of the Daleks is somehow permeating through time and getting into people's consciousness. He recalls the voices that he and Nyssa heard earlier, but none of it makes any sense. Tillington is worried there could still be a Dalek invasion, and the existence of the Dalek toys is making him extremely nervous. How to make sure the invasion never happens is something the Doctor and Tillington's technicians need to work out between them, but once they have access to the Doctor's time technology they'll have a better chance of getting some answers. The Doctor flatly refuses to work for the General, claiming he has broader responsibilities. He agrees that there's something wrong with time that needs to be solved, but when he promises to do everything he can to "put things right", Tillington becomes suspicious again. He's already established that the Doctor was involved in the alternative timeline in which the Earth was invaded, so from the Doctor's perspective that is obviously the correct path for history to follow. However, the General has no intention of letting the Doctor change things back. Tillington is only interested in the well-being of this planet, and he insists that the Doctor help them. When the Doctor still refuses, the General orders him to be arrested and strip-searched, then placed in a segregated maximum security cell on Level 5.
Mulberry asks Nyssa why she's whispering into the device she holds, but when she starts to lose her footing he climbs up onto the parapet with her. She regards the Knights as nothing more than armed thugs, so the closer he gets, the faster she backs away. He reaches out a hand to help, but the stones beneath his feet are loose. Before long, it's Nyssa that's offering a hand to help Mulberry, but the parapet begins to crumble under their combined weight and they both fall off and plummet hundreds of feet to the stone courtyard below...
Imprisoned in a cell, the Doctor calls for attention. He assures his captors that he's not actually refusing to help solve the mystery of the Dalek non-invasion, but whatever happens, he's not going to be able to do much if he remains locked up. He becomes angry and seems quite prepared to continue shouting until they see reason. Suddenly a voice whispers to him from the shadows. A young man appears outside the cage and tells him he's short-circuited the surveillance. They only have a minute before the power is restored, so as soon as he unlocks the door, he's going to need the Doctor to run as fast as he can...
The screams of Nyssa and Mulberry come to a sudden stop as their bodies smash into the ground. It's immediately clear that something very strange is going on as they're both relatively unscathed, despite the long drop. Nyssa tries the pocket interocitor and isn't surprised when it doesn't work. Mulberry is trying to reason things out -- he knows they fell at least the height of fifteen men onto cobblestones, yet now they appear to be on top of a hill. It was also night when they fell, but now it's daylight. The Knight suspects that Nyssa's device has somehow bewitched them, but frankly she doesn't think it does anything at all. She asks him if he's ever fallen through a wormhole, but of course he's unfamiliar with the term. She explains that somehow there's a traversable topological anomaly in space-time connecting Rhodes in 1320 to wherever they are now...
The Doctor and his rescuer escape from the compound and approach a flying machine parked nearby. There's barely enough room for both of them inside and the Doctor is particularly concerned that there isn't room for them to take off, but the young man tells him that one of the neat things about a skyscooter is that they can take off backwards. The Doctor holds on tight as the man pilots the machine into the air.
Nyssa and Mulberry hear some commotion coming from further down the hill, so Nyssa advises the Knight to keep his head down until they know where they are. Moments later, he reports back that he can see about two thousand soldiers surrounding the hill, but he's noticed they aren't wearing any armour, so she advises him to get rid of his own. As she helps him, she wonders what the soldiers are doing here, and Mulberry guesses they've come to engage in battle with other soldiers who are already on the hill...
The Doctor's rescuer tells him that they're taking a low flight-path along the river to avoid being completely fried by the Global Warning defence system. The young man introduces himself as Wilton and says he knows about the Doctor because his uncle was planning to have tea with him. The Doctor realises that Wilton's uncle must be General Tillington, but the only reason Wilton can give for rescuing the Doctor is that his uncle would never agree to let them meet. The skyscooter approaches Blackfriars Bridge, where the TARDIS landed; Wilton recognises the name of the TARDIS because he sneaked a look inside his uncle's case while Tillington was busy lecturing him on the merits of responsible behaviour. He brings the skyscooter in to land just by the wharf, but when the Doctor thanks Wilton, the young man grabs his bag and invites himself for a trip in the time machine. The Doctor is about to argue with him when machine-gun fire rings out. Tillington's men have spotted them and the Doctor has no choice but to allow Wilton to join him aboard the TARDIS. Once inside, the Doctor orders the young man to stand in the corner and not touch any of the controls.
On the hill, Nyssa and Mulberry watch as two armies fight each other. The soldiers are using rifles, which Nyssa deduces puts them somewhere in the 19th century, but unfortunately she and Mulberry seem to be caught in the middle of the action. Before long, a voice calls out to them and they see a dark-skinned man limping towards them. Mulberry pleads with Nyssa to use her witchcraft to save them, but the man only seems to be interested in whether they're civilians. Nyssa tries one more time to contact the Doctor using the pocket interocitor, but the new arrival orders her to put the machine down or else he'll take her head right off. Fortunately the only 'weapon' he has is his crutch, but it's clear he thinks Nyssa's device is some sort of bomb. Suddenly a shot rings out and the man falls to the ground, clutching his shoulder. Nyssa asks Mulberry to help the injured man while she tries to summon the Doctor again. At first the Knight refuses on the grounds that he's the enemy, but Nyssa reminds him that this isn't their war.
Inside the TARDIS, the Doctor starts scanning the databanks. Wilton spots a red light flashing and alerts the Doctor in case it's something urgent, but the Doctor hates being interrupted when he's busy. He mentions the Dalek invasion that never was, which reminds Wilton that he has a present for the Doctor. He opens his bag and pulls out a cardboard shoebox, but just then the Doctor notices the red light and rushes over to activate the interocitor's message notifier. He switches it on and hears Nyssa's voice calling for him, with gunfire echoing in the background. There's evidently a war going on and Nyssa tells him she's in Petersburg. The Doctor realises they're listening to sounds from the 1860s -- which means she's got herself caught up in the American Civil War!
Nyssa and Mulberry help carry the injured soldier, who identifies himself as Floyd, to the relative safety of the picket line. It's getting dark and Floyd confirms that the rifle fire usually stops at night time, but the heavy ordnance is likely to continue. He cries out in agony again, but bravely struggles on, acknowledging the first aid provided by Mulberry. He takes them to a hole hidden behind some bushes where they're able to rest. He recommends they stay there until dawn as they don't want to go crawling through a minefield in the dark. Floyd sounds almost impressed by the different methods of killing that the smart engineers have invented, but when Nyssa assumes he's a Confederate, he explains that he currently doesn't have a master, since his previous owner was killed during the same incident that injured his leg. Mulberry notices that Nyssa's 'witch-box' has started glowing, which tells her the Doctor is trying to get through with a message.
Despite being ordered not to by the Doctor, Wilton has been checking Petersburg on the TARDIS databank and discovers they should head for 1864. Unfortunately the fighting went on there for nearly ten months and they can't narrow Nyssa's location down to a specific date, but then another message starts coming through from Nyssa which reveals that she's on a hill called Elliott's Salient. Nyssa still can't hear him, but he can hear her and that's all that matters. There's a time stamp on the message showing her temporal location as 3.14am on July 30th. The Doctor hurriedly programmes the TARDIS and within moments the ship has landed. He cautiously edges the door open, but outside everything sounds peaceful. This is odd, so he tells Wilton to stay inside while he goes out to explore. Despite further orders not to touch the console, Wilton can't resist checking the databank again. He confirms they're in Petersburg, but there's no sign of Elliott's Salient. Realisation suddenly dawns on him and he rushes to the door and calls out to the Doctor. He knows why there's no battle going on outside -- the ship has brought them to Petersburg in Grant County, West Virginia! It's the wrong Petersburg and they're in a different state completely. The Doctor races back to the controls and identifies a minor data corruption in the location finder. He hurriedly tries to re-programme the ship for the correct location...
As they wait for the Doctor to rescue them, Mulberry asks Nyssa whether he'll be bringing medicine to help treat Floyd's wounds, but Nyssa tells him he's not that kind of doctor. Floyd isn't complaining, but Mulberry can see that his leg is smashed to the bone and infected with plague!
The Doctor has finished checking the console, but he hasn't been able to find anything wrong. Once again he spots Wilton taking too close an interest in the databank, but this time he's found something of interest -- the entry for the Battle of Elliott's Salient refers to a mineshaft under the Confederate lines which was blown up. It says the "fuse was lit" on the morning of July 30th at 3.15am. This means Nyssa is sitting on the very spot that exploded -- and according to these records, it happened thirty seconds ago!
The Doctor finally realises why Elliott's Salient rang a bell, but Wilton thinks that because the TARDIS is a time machine, they can just wind back the clock and fix the problem. The Doctor climbs underneath the console and checks the time track crossing protection protocol, a pre-set circuit found on all TARDISes. He hasn't looked at it in years, so the connections are a bit dodgy, which means although the protocol is supposed to be constantly engaged, the truth is it sometimes isn't. He explains that if someone re-visits the same space-time location more than once, the recursion effects can have completely unknown and unpredictable consequences. The protocol is supposed to prevent that, which would stop them going back to Petersburg at 3.14am, but strictly speaking they haven't actually been to that place yet. If the Doctor can override the protocol they might be able to save Nyssa, always assuming they don't vanish into the temporal nullity first.
As explosions go off around them, Nyssa checks on Floyd's condition. Mulberry tells her he's still alive, but probably not for much longer. Nyssa is furious with the interocitor for letting her down and calls desperately for the Doctor to rescue them. Mulberry feels that she's somewhat lacking as a witch and she agrees that a flying broomstick would come in very handy right now. Suddenly the TARDIS materialises and the Doctor urges everyone inside. They only have seconds to spare, so the introductions are brief, but he agrees to allow the two extra passengers on board. He calls for Wilton to help carry Floyd inside while he goes back inside to arrange for an emergency take-off.
Inside the TARDIS, Nyssa thanks the Doctor for finally turning up. Mulberry offers to tend to Floyd's wounds, but the Doctor suggests they take him to the new Zero Room, which is ready at last. Before they can do that, there's a huge explosion outside the ship and the scanner image shows first flames and dust, then a huge crater, thirty feet deep and 170 feet across. According to the databank, about 300 Confederate soldiers died in the blast, and Nyssa realises how lucky they've been. The Doctor asks Floyd who he'd like to win the war, and when the injured man says Confederates, the Doctor tells him to look at the screen. They watch as the Union Army rush forward to take Elliott's Salient, but then the soldiers start tumbling down into the crater, helpless. What they're seeing on the scanner is the massacre of an untrained Union division who thought they were off duty but were rushed into battle and became open targets for the surviving Confederate soldiers. Floyd starts to whoop with delight, but the Doctor is sickened. War is horrible enough, but incompetent war is an abomination.
Later, Floyd accompanies Nyssa and Mulberry deeper into the TARDIS and tells them he thought the Yankees got what they deserved. Suddenly he stops when he catches something out of the corner of his eye. Nobody else noticed anything, and he can only describe what he saw as "scurrying things like big steel rats". The others assume he must be hallucinating from the fever, so Nyssa hurries him towards the Zero Room.
In the control room, the Doctor stumbles over the unopened present that Wilton gave him earlier and he angrily tells the young man to take the shoebox away. Wilton has been reading up about the Daleks in the TARDIS databank and asks the Doctor what makes him think there was ever an invasion. The Doctor reminds him that he was actually there during the occupation of Earth. He wonders how much Wilton knows about his uncle's work, but the young man's answers are vague.
Mulberry is amazed at how calm the environment inside the Zero Room makes him feel. Floyd can't shake the feeling that the things he saw in the corridor were coming for him, but Nyssa assures him he's safe in here. He thanks her for her concern and describes himself as a worthless slave, but she insists that's not true. Even Mulberry acknowledges that every slave has a value in the marketplace, but that wasn't the kind of support she was looking for. Nyssa recalls that the war they just left was all about freeing slaves, but Floyd believes it was more about fighting for the Constitution and for sovereignty of the States. Nyssa can't understand why people would fight for such a thing, but Floyd points out that words like right, justice, liberty and freedom are important. Nyssa realises he sounds just like the voices she heard earlier, and she tells them she discovered some pockets of space-time filled with whispers. Mulberry has heard them too, speaking about things like the "great peace", and then Floyd also recalls an occasion when he heard them. Nyssa tries to question Floyd further, but by now he's fallen asleep.
The Doctor discovers that the TARDIS is travelling on a fixed course of its own, and he's unable to switch the time track crossing protection protocol back on. Suddenly, he hears the chilling voice of the Daleks declaring themselves to be the supreme beings in the Universe. He tracks it down to Wilton's shoebox and opens it to reveal a toy Dalek, similar to the one General Tillington showed him earlier. Wilton explains that everyone in school has been collecting them since last year. The Doctor demands to know why he brought it with him, but once again the young man seems very vague and says he just thought it would be a good idea at the time. The Doctor isn't surprised that he has no explanation, just as there's no logical explanation for the toy Daleks being manufactured in the first place.
Nyssa returns to the control room with the news that the Zero Room is doing its work on Floyd. Rather dramatically, the Doctor tells her they're probably plunging to their doom -- but there's an even more pressing problem. He shows her the toy Dalek which Wilton brought aboard. This is the first opportunity Nyssa's had to enquire about Wilton's presence aboard the ship, so the Doctor gives her a brief rundown of his earlier encounter with Tillington. He tells her that Wilton comes from 2158, a period which, according to established history, should involve incurable plagues and meteor bombardments. It was the start of an occupation that lasted ten years, but now someone has changed what happened. He explains that after he dropped Nyssa off, the TARDIS's chronometer went haywire so he had to make a random landing. When he went outside to establish the date, he found himself in 2158 -- but with no Dalek invasion. Tillington is the head of Global Warning, an organisation that has time technology several centuries before it should, and it was predicting another imminent Dalek invasion. Nyssa wonders if it has anything to do with the voices she's been hearing and the Doctor thinks it would be too much of a coincidence if it hasn't. She realises he wants to put history back on the correct path, but Wilton is horrified that he would condemn them all to a horrible plague and invasion. The Doctor points out that the alternative invasion could be a thousand times worse. He checks the chronometers again, but there are still no readings. When Wilton mentions the protection protocol, the Doctor realises the Daleks don't have such a system, so their time journeys can overlap. Every overlap causes an intersection and every intersection potentially causes an anomaly. After their occupation of Earth was repelled, the Daleks must have doubled back on themselves and tried again, and somehow the notion of Dalek-ness is permeating through time. The only way they can find out for sure is to find the Daleks and stop them. The Doctor has to risk everything by forcing a materialisation so they can get their bearings and find out exactly where they are.
The Doctor and the others explore outside the TARDIS. The ship has landed somewhere warm and wild and they have to fight their way through the undergrowth. Wilton thinks it's beautiful, but the Doctor warns that it might be dangerous as well and you can never really tell with jungles. Fortunately Floyd's leg has fully recovered and he's the first one to notice a river beyond the trees. As they move in for a closer look, the Doctor identifies the plants as wild rice and concludes they're in South Asia. They hear the approaching sound of helicopters with what appears to be smoke coming out of them. The Doctor tells them it's Agent Orange and urges everyone to take cover, but then gunfire shoots out from the bushes and the group find themselves in the middle of a battle between American troops and the Viet Cong. This is the Vietnam War! Jets arrive in the sky to provide air cover for the helicopters, giving the group an opportunity to run back for the TARDIS. One of the helicopters gets hit by gunfire and crashes to the ground, but the group can see someone still alive inside, so the Doctor takes Mulberry to investigate while Nyssa takes Floyd back to the TARDIS.
Major Alice Hunniford is the surviving pilot aboard Cobra 3. She tries to contact her base for assistance as she's stuck inside the burning helicopter, and is surprised when the Doctor politely knocks on the window and promises to get her out. With Mulberry's help he manages to release her, and despite her broken ankle, her only complaint is about the friendly fire from her own side that caused the crash in the first place. With the gas tank about to explode, the three of them get clear and head for the TARDIS. Once inside, Alice explains that the Agent Orange kills all the vegetation that the enemy use for cover, but the thought that soldiers are waging war against grass and leaves amuses Mulberry. The Doctor asks Floyd and Mulberry to take their new friend down to the Zero Room, and the sight of her new environment leads Alice to believe they must be CIA agents. Just for a moment the Doctor and Nyssa hear the faint whisper of voices again, and this time, Wilton hears them too. The Doctor suddenly realises that the toy Dalek that was left on the floor has disappeared, but Wilton misunderstands his concern and tells him it doesn't matter as he brought two more with him in his backpack. However, when he goes to get them he finds they too have disappeared.
Alice is amazed at the size and scope of the TARDIS, but Floyd and Mulberry are unable to answer her questions as they're new here too. Floyd questions what sort of army would send ladies out to fight, but Alice admits that defoliation is considered non-combatant. Mulberry explains that the Zero Room has magical qualities, which Floyd demonstrates by leaning backwards and levitating into the air. They encourage Alice to do the same so that the room can get to work on her ankle. The effect starts straight away and she finds herself becoming drowsy. She allows herself to drift slowly off to sleep, although she remains resolute that there's still a war out there to be fought and mumbles about freedom, justice and honour. Her words remind Mulberry of the voices that came to his people's aid during their fight against the forces of Rhodes by filling their minds with icy fire. He believes that his people freed the population from their own backwardness so they could build it into a great civilisation. Floyd decides to stretch his legs by exploring the rest of the TARDIS. Mulberry reminds him that the Doctor told them not to wander off, but Floyd is now a free man and is growing to like the idea that he can go wherever he wants.
The Doctor has concluded that the voices are transmissions and is now using a tracker to find out where they were aimed. The device is picking up actinoidal energy, which surprises Wilton, as the atomic table shows the actinide series to be radioactive metals. Nyssa assures him there's nothing to worry about as they're talking about time-suspended actinide, which means the energy can be used to power devices like the toy Daleks. The Doctor's tracker leads them to one of the toy Daleks in a nearby corridor, and when it turns and moves away, the three of them decide to follow it.
In the Zero Room, Mulberry listens as Alice continues to mutter in her sleep about serving her country, right or wrong, and he realises the voices are soaked into her very soul. Suddenly the door bursts open and Floyd races back in, distressed at seeing "voodoo creatures" stalking the corridors. They had voices like a rusty gate and were giving him orders. His shouting wakes up Alice, so she and Mulberry agree to investigate the metal creatures...
The Doctor, Nyssa and Wilton race through the TARDIS corridors in an attempt to catch up with the miniature Dalek. They soon find it, but every time they get closer, the toy increases its speed. Eventually the Doctor calls the others to a halt and they discover the Dalek also slows down to match their speed. The Doctor realises it's been leading them away from the console room on purpose, and Nyssa points out that the other two Daleks could have doubled back. The Doctor agrees and they race back in the direction they came from. The tiny Dalek starts to follow them and orders them to halt. Confirmation that the Dalek is definitely more than a toy comes when it starts shooting at them, so the Doctor recommends they don't hang around to find out whether it could harm them.
Back in the console room, the other two Daleks report that interface with the TARDIS is now complete and the co-ordinates are set. Moments later, the power source is engaged and the ship changes course. The Doctor and the others arrive and find the two remaining Dalek toys on top of the console. Angrily, the Doctor tries to sweep them off, ignoring Nyssa's warning that they could be dangerous. One of the Daleks orders him to remove his hand immediately, but he ignores it and tries to pull them free of the controls. Suddenly a charge of power shoots out towards the Doctor and his friends realise he's being electrocuted...
The Doctor reassures Nyssa that the Daleks don't have enough power to make the electric shock lethal, just very uncomfortable. His friends try to drain the charge off by linking hands and forming a chain with the Doctor at the end. The power starts to deplete and eventually the three of them are able to pull the Dalek away from the console and break the connection. The Dalek drops to the floor and appears to be broken, but when they turn their attention to the other, they find that it's already gone. The one that had been following them has also disappeared, and the Doctor concludes that they've already achieved what they came here to do. Seconds later, Floyd, Mulberry and Alice arrive in the control room and confirm that they saw the tiny creatures shoot past in a hurry. The Doctor picks up the pieces of the broken Dalek and considers his current position. He has a TARDIS full of strangers and the ship has been locked on course to an undisclosed destination by a couple of toy Daleks. He asks Wilton to join him in the laboratory while Nyssa stays behind to see if she can work out where they're going. Meanwhile, he's going to look for some answers to the many questions building up. There's not much Alice, Mulberry and Floyd can do but wait, so Alice decides to pass the time by checking the flight manuals in the TARDIS databank.
In the laboratory, Wilton asks the Doctor about actinoids. From what Nyssa said earlier, he knows they're radioactive metals that are somehow frozen in time so that they preserve their energy instead of decaying, and he guesses that the toy Daleks must be able to tap into that energy. The Doctor confirms this and says they'd need some kind of time conduit built into the actinoid to control the energy release. The Doctor wonders whether General Tillington's time technology facility was working on something similar to his own pocket interocitor. He accuses Wilton of spying for his uncle -- how else would he have been able to rescue him from the jail or force his way onto the TARDIS with the flimsiest of excuses? Wilton denies this and says he recognises the name of the interocitor from an old sci-fi movie, This Island Earth, which the Doctor admits was his little joke. Wilton has read about quantum entanglement but he doesn't understand how it could be used for temporal communication. The Doctor explains that if you split two quarks you end up with two sub-particles that behave as if they're in communication, even if they're separated across time and space. He admits that it's a philosophical impossibility and Wilton unwittingly reveals that his uncle's experiments in this field are nowhere near as advanced. Somehow the Daleks are using this technique to transfer power and instructions to their toy counterparts.
Alice races into the laboratory with an urgent message from Nyssa. They return to the control room, where Nyssa tells the Doctor that she thinks the TARDIS has begun travelling sideways through time! This is a potential calamity and they soon increase speed even faster. It doesn't seem to be causing any damage to the ship, which suggests that whoever is behind the voices wants them to arrive in one piece. Alice admits that she too has heard the voices in her dreams and both Mulberry and Floyd add that they've been hearing the voices all their lives. The Doctor theorises that the voices become less of a conscious phenomenon the more the human race develops. When Nyssa first started hearing them inside the TARDIS, the Doctor called her Joan of Arc, suggesting that the voices Joan heard telling her to chase the English out of France were genuine and deadly serious. These voices were what encouraged Nyssa to develop a way of tracking them through time in the first place.
They activate the pocket interocitor to see if they can pick anything up. They hear a babble of confused voices talking about the causal nexus, fundamental truths, natural justice, the absolutes of time and space, and the fight for freedom. Before they can work out what the messages mean, the TARDIS seems to hit something and everyone holds on as the ship starts to shudder violently. When it eventually stops, the Doctor confirms that control of the ship has been restored. Nyssa points towards the scanner and they realise they've landed on another planet where the whiteness of the landscape glowing under the light of hundreds of suns is overwhelming. Wilton thinks they must have arrived in a parallel Universe, but the Doctor says that can't be right and this must be the point where all the time tracks converge. The iridescence is beautiful, but Floyd spots something on the edge of the shining -- either a blue mountain or a vast city of some sort. Nyssa checks the console and confirms that it's built of non-natural artefacts. The Doctor decides to go out to explore and leaves Nyssa behind in charge of the others, although he nominates Alice as 'chief advisor' to keep her happy. Alice offers to provide the Doctor with cover, but he informs her there are no weapons aboard the TARDIS. Nyssa passes him the pocket interocitor and he steps outside.
The light is so bright it takes him a while to get accustomed. He views the structure in the distance and agrees that it looks like a city, but as he moves away from the ship his voice completely fades away. Inside the control room, Nyssa and the others are suddenly distracted by the return of the two toy Daleks, who now have a direct connection to their power source. The Doctor shouts out from the distance and invites the others out, but the Daleks order the group to surrender and to evacuate the ship. One by one the group files out, joining the Doctor outside. The Daleks order the group to accompany them back to the city, but suddenly Alice calls to the others to get back into the TARDIS. She manages to get inside with Mulberry and Floyd before the Daleks can open fire. They slam the door shut behind them and the Daleks realise there's nothing they can do to get them out again. The Daleks dismiss them as primitives from ancient history and, confident they can do no harm, order the Doctor, Nyssa and Wilton to follow them. Nyssa observes that the ground they're walking on is like snow, but Wilton compares it to solid cloud. The Doctor is starting to wonder whether Wilton was right about philosophical impossibilities -- perhaps this place isn't really here. The Daleks order them to be silent, but the Doctor knows they have orders to take them to the city, so he'd be astonished if they were allowed to exterminate their prisoners. Wilton wonders why they don't just make a run for it, but the Doctor advises against it. Instead, he switches on the interocitor and announces that it's time for a little song.
Inside the TARDIS, Alice is frustrated that she couldn't save the whole group. On the scanner they see the Daleks driving the others across the landscape like sheep, and Alice declares this to be a hostage situation. They continue watching until the Doctor's group fades away into the whiteness, then Alice orders Floyd and Mulberry to search the place for anything useful. Unfortunately they can't find anything they'd recognise as a weapon, so Alice decides to fall back on Plan B. Nyssa mentioned earlier that there was a manual in the databank query system, so Alice begins searching for flying instructions. Just then, they start to hear voices again, but not the same as the ones they heard before. This time they're coming from the speaker. Alice turns the volume up and they're amazed to hear the Doctor and Wilton singing Three Blind Mice.
Back on Earth, the Sergeant reports to General Tillington that something is coming through at last. The technicians have spent 33 months developing the temporal communication technology and they've finally picked up a signal, although the temporal and spatial locations are still unidentifiable. The signal is still weak, so they work on the correction filters -- until eventually they make out the sound of people singing Three Blind Mice...
Wilton tries to encourage Nyssa to join in with them, but she insists they have nothing to sing about. She thinks the situation is serious and all they're doing is annoying the toy Daleks, but the Doctor seems to think that's good and puts in a request for one more chorus. He and Wilton begin the song again.
In the TARDIS, Alice is amazed to hear her fellow travellers singing such a screwy song... but then starts to realise it might be some sort of battle code. Perhaps they're sending a message to get out of here. Floyd thinks this is unlikely -- he thinks the Doctor is singing loudly to get their attention. The song itself isn't the message, but that will come later once they start listening.
The Doctor thinks they'll be at their destination in another couple of minutes. Wilton wants to rest and when Nyssa advises him not to disobey orders, he reminds her that the Doctor said the Daleks can't kill them. However, the Doctor stresses that although the Daleks won't kill all of them, at least one of them might be considered dispensable. Wilton doesn't have to think too hard to realise which one... As they reach the city, they realise the towers are made of full-size Daleks, millions and millions of them stacked up together and bonded like molecules until they reach the sky! The Doctor wonders whether this is evidence of the Daleks' slave mentality, or perhaps it's just a cheap and easy way to create large building structures. The group is approached by another group of full-size Daleks who have come to escort them into the city. They notice that these Daleks are behaving in a rather odd way, almost neighbourly, and Nyssa suggests they might feel more confident now they're at home. This hadn't occurred to the Doctor and he begins to wonder whether the Daleks have made this place their new home.
The others travellers have been listening to this conversation in the TARDIS. Alice suggests they leave straight away, but Mulberry and Floyd feel it is their duty to remain and help free their comrades. Alice points out that the right thing to do in these circumstances is to obey a superior officer -- herself -- but Floyd angrily replies that she isn't his superior and he's not even part of her army. Their debate soon descends into an argument about who won and lost the civil war, but Mulberry interrupts and warns against the dangers of quarrelling amongst themselves. He asks Alice if she's confident about controlling the TARDIS, but she's still having problems getting clearance to use the instruction manual.
The Daleks confine their prisoners, which goes against with the Doctor's 'neighbourliness' theory. The prisoners find themselves in pitch darkness, although there's still enough light coming from the interocitor to light up the immediate area. The very walls themselves are constructed from hundreds of interlocked Dalek shells, but it's not possible to be sure whether there are creatures inside or whether they're just empty battle casings. The Doctor compares the structure to Logopolis, and Nyssa tells Wilton about the planet of mathematicians who sat in rows of caves carved into the rock. Their incantations were computations, passed from one to another down the line. The Doctor is more interested in their current situation and says they need to work on a plan... or a plane... or a planet. Earth, for example, would be a useful planet to have to hand right now.
Back on Earth, General Tillington recognises the Doctor's voice, which is confirmed when Nyssa accuses him of rambling. The Sergeant arrives with news that Global Warning has gone to red alert. World-wide authorities have already been informed and their time sensitives are starting to visualise the Dalek invasion more solidly. The General tells him they need to get a message to the Doctor as he's the only one that can help them now. The Sergeant says they're working on it, but Tillington insists they get it working right now!
Alice has also been listening to the Doctor's reference to a plan, a plane or a planet, and she wonders whether he's gone insane. The Doctor continues to babble about how important it is to have a pupil to teach the plan to, and how the plane requires a pilot. If they had a plan, a plane and a planet, along with a pupil, a pilot and some people, they might make some headway. Alice dismisses the message, but Floyd insists that he's using a kind of code that the Daleks won't understand. When they stop to consider what they've heard, Alice accepts that she might be the pilot he's referring to, and Floyd assumes he must be the pupil because the Doctor had mentioned how smart he was. That would mean the plane is the TARDIS... but what exactly are they supposed to do? They listen in for further instructions and find the Doctor and Wilton have started singing Three Blind Mice again. Floyd realises this is now the message itself -- they need to fly blind. Alice starts looking to see if the TARDIS has an auto-pilot system.
The two Daleks who are standing guard start to take an interest in their prisoner's bizarre behaviour, so the Doctor urges Nyssa to hide the interocitor. Just then, a door opens and the three prisoners are blinded by a bright light. Something enters the room, and although it appears to be humanoid, Wilton describes its appearance as gross. Nyssa hopes the creature didn't hear what he said, but it addresses her by name and tells her it can hear everything that is said in every language. It introduces itself as the Greylish.
The Doctor introduces himself, but the Greylish already knows him and claims they've met before. The Doctor denies this, but the Greylish reminds him that this is the place where all time tracks meet, so to come here once is to come here always. He says the Doctor has always been here and the two of them know each other very well by now. The Greylish leads the three of them into a huge, vast space, although the expanse isn't really space at all, but time. They're on an island of time carved out of the dimensional nullity. This is the Dome of Time and he's allowed it to become the Daleks' foundry, confirming the Doctor's suggestion that the Daleks have made this place their home. It's like a huge cathedral filled with booths containing models, diagrams and even battle plans, as if they were at an exhibition. They're standing in the middle of a Dalek battle base!
Alice finds the activator control and checks that it's set to autopilot. This should enable the TARDIS to track in on the homing signal that the Doctor is sending out. She's reasonably confident she can put the ship in motion now, but who knows where it will end up? She activates the control and eventually the time rotor comes to a halt and the ship appears to be stationary. Alice tells the others to cross their fingers. The three of them emerge from the TARDIS and shut the door behind them. Floyd treads on something just beneath the surface of the 'snow' and he discovers it's the interocitor that Nyssa hid earlier. It's not exactly a weapon, but it might come in handy. Mulberry is keen to rescue their friends, but Alice won't be rushed and wants to scout out the area first.
The Greylish explains that this world is the Pan-Temporal Ambience, a vantage point from which he can see the whole chronology of folly. It's basically an overview of the history of war, hence the time tracks between the wars in Rhodes, Petersburg and Vietnam. The Doctor wonders why the Greylish would want to monitor the history of human aggression, as there's already enough evil contained in the Daleks. The Greylish considers this to be a narrow judgement, and claims that the Daleks have observed and learnt about the need to inspire and encourage. The Doctor realises the voices they've been hearing are some form of mental conditioning, preparing mankind and making their minds receptive to Dalek thoughts and concepts. The Greylish confirms that the voices are actually trillions of Daleks communing with one another and says it took all the power of their structured mind-share to devise this renaissance of the Daleks. He introduces them to the Dalek project leader, who offers to explain their story and show them how the process works.
First, they must go through the Cleansing Chamber in which an air stream removes any contaminants from their bodies. When the Doctor mocks the Daleks for being 'perfect', the project leader declares that in the course of their history the Daleks have learnt to extend their inherent capabilities. They've managed space flight and time travel, yet the Doctor points out that there's been no actual evolution of the Dalek creatures themselves. They still have the same Dalek brains at the core of their battle shells, so what's new? The project leader argues that the Dalek design has proved equal to all challenges, but now they have augmented it and it's all a matter of scale. Wilton assumes they're referring to the toy Daleks, but the Doctor realises it's something more than that. The Daleks are using actinoidal energy to control the toys by transmitting that energy across space and time. But why use the voices to create certain conditions on Earth that would make humans susceptible to Dalek concepts? Why manufacture billions of empty toy Daleks with actinoidal energy receptors? And why make something empty unless they intend to fill it? They arrive in another chamber and see a production line processing tiny dust particles. The Doctor theorises that it's a possible virus, but when he increases the magnification on the screen, the truth slowly dawns on him...
As Alice leads the others through the corridors, she rebukes the others for talking too loudly, but they both insist they never said a word. It soon becomes apparent that the voice is coming from the interocitor in Floyd's pocket. They listen to it and hear General Tillington calling for the Doctor. Alice snatches the device and speaks to Tillington, who explains who he is and where he's calling from. As Alice finishes listening to General Tillington's instructions, the Daleks arrive in the area and order them to surrender.
The Doctor and Nyssa are shocked to discover the production line is producing nano-Daleks. The Greylish explains that they all originate from one living Dalek, which had been perfected over generations of breeding. The seed Dalek is copied to a replicator tube and the copies then pass through a re-sizing matrix. Each miniature Dalek creature is protected from the environment by its scaled-down battle shell. The voices have done their work and now the Dalek invasion of Earth can take place bloodlessly. The nano-Daleks will be disseminated from the Dalek toys and will enter each and every human on Earth. All human brains will be receptive to Dalek commands and they will become their willing, contented slaves. Wilton confronts the Greylish and asks why he helped the Daleks achieve this, but the Doctor is more interested in why the creature is demonstrating their plans to him in such detail. A Dalek arrives with the news that more prisoners have been captured and orders are given for them to be exterminated. The Doctor objects, and the Daleks tell him he must obey all their commands or they will go ahead with the execution.
On Earth, all red-alert contingency conditions are deployed and a permanent worldwide curfew is imposed until further notice. There's nothing more Tillington's team can do now, especially as their TLTs are unable to give any more information about when the invasion will happen. The only thing they can do is wait to hear again from the Doctor...
Alice angrily demands that the Daleks take her to see their commanding officer, but the Doctor warns her not to antagonise them. Wilton is impressed that they managed to get the TARDIS to work and even the Doctor admires the infinite resourcefulness of the human race. A group of Daleks arrive carrying large black caskets, and announce that the prisoners will be allowed to return to Earth on condition that they take the caskets with them. The Greylish tells them that a time track is being prepared and a time corridor will send the TARDIS to the exact point in time and space when the new invasion of Earth will begin. The Doctor assumes the crates are full of nano-Dalek dust, but Nyssa points out that they should have no need for the crates if they're planning to transmit the dust across time and space into the Dalek toys using actinoidal energy. She suddenly realises the Daleks are stuck for bandwidth. There's a limit to the quantity of nano-Daleks that each toy can handle and even if there are millions of toys back on Earth it'll take far too long to achieve a useful concentration. Using the TARDIS they can deliver billions of nano-Daleks all at once. The Doctor confronts the Greylish and asks him whether he will allow such a major upheaval in time, but although the Greylish says he has no views on this as he is only an impartial moderator here, he does point out that the original invasion only failed because of the Doctor's intervention. The Doctor himself is an outsider, meddling in the shape of the time tracks, so he can hardly blame the Daleks for wishing to rectify the situation. The Daleks report that all the crates have been loaded into the TARDIS, so now it's time for the Doctor to operate the ship. If he refuses, they will execute his friends one by one until he changes his mind. Suddenly the Doctor orders everyone to rush into the TARDIS, and before the Daleks can react all the prisoners race inside and shut the door behind them.
The Doctor and the others pause for breath as the Dalek leader appears on the TARDIS scanner to mock them. The Greylish confirms that the Doctor has done exactly what the Daleks predicted he would do, and the Doctor reminds his friends that as soon as he dematerialises the ship they'll be stuck in the time corridor. The Dalek leader tells him the crates are programmed to burst through the spatio-temporal shell of the TARDIS the moment it completes its materialisation. Nyssa wonders if the Daleks have the power to destroy the ship, and the Doctor suspects that they may have. The only flaw in their plan is that they're not allowing for him to just sit here for eternity. In a sense, by just standing there and doing nothing, he's defeated them. Although the Daleks are already transmitting some of the nano-Daleks down the time tracks into the toy Daleks, Wilton's uncle is already expecting a Dalek invasion and if it happens too slowly, he might find a way to defeat it. The Daleks remain convinced that the Doctor won't be able to resist trying to defeat them, but the Doctor knows they're just trying to goad him into action. However, when Alice informs him that they've just been speaking to Tillington on the interocitor, the Doctor surprisingly accepts the Daleks' challenge. Before he goes, he poses a thought for the Greylish to ponder. If his Pan-Temporal Ambience truly exists in all times at once, and if he genuinely allowed the Daleks to make this place their home, then he should presumably know of a time before the Daleks arrived. Then the Doctor decides it's time to fall into the Daleks' trap and sets the TARDIS on course...
On Earth, an alarm sounds in the Shaping Chamber, indicating that the pre-constructions of the time sensitives have become solid. They now have an absolute fix on the Dalek invasion at 1835 hours, which is just over fifteen minutes from now! Before General Tillington has a chance to react, the Doctor's voice comes through on the holographic display. He asks the General if their laser defences can be targeted at the exact position near Blackfriars Bridge where the TARDIS first landed. When the General asks what they'll be firing at, the Doctor tells him they must aim at the TARDIS itself. The moment he sees the ship starting to materialise, he's to open fire and blast it with everything he's got. Tillington hears the voices of the other passengers, including his own nephew, protesting to the Doctor, but the Doctor insists there isn't time to argue as the Daleks are using his own ship as the invasion spearhead. Tillington understands the situation and tells the Doctor he's a brave man. When the Doctor switches off the interocitor, Mulberry agrees that it's brave to sacrifice his own life, but Alice points out that they'll all be dying with him. Nyssa is confused as the TARDIS can't be destroyed by laser beams and the Doctor confirms this, but he's hoping the lasers will trigger the HADS -- the Hostile Action Displacement System -- which means the TARDIS will instantly dematerialise if the outer shell comes under attack and relocate the ship at a randomly selected safer landing spot. If Tillington fires fifty gigawatts of power at the TARDIS the moment he catches sight of it, they'll automatically relocate before they've properly landed. They should have about thirty seconds grace in the Time Vortex before they land fully and the crates burst out, and during those thirty seconds they must somehow regain control of the TARDIS.
As soon as Tillington catches sight of the blue police box arriving on Blackfriars Bridge, he gives the order to open fire. The laser shoots out with a tremendous power -- and inside the ship, the Doctor confirms that the HADS is engaging. He urges everyone to hang on -- the TARDIS has temporarily gone back into the Time Vortex and he's about to open the doors! Suddenly everyone feels themselves being dragged towards the entrance, but unfortunately the crates themselves don't appear to be moving and, if anything, they seem to be activating. If the Doctor doesn't do something soon, the crates are going to explode. Mulberry lets go of his grip and drops down onto the crates. The Doctor and Nyssa urge him to stop or he'll be sucked out, but the Knight turns to Nyssa and asks her if this is the way to save the world. She refuses to answer, but they hear the sound of the TARDIS engines as the ship starts to relocate to another landing spot. Mulberry asks his question again and reluctantly Nyssa confirms that his actions will indeed save the world. Mulberry says goodbye, then forcibly edges the crates towards the open doors. Caught up in the drag, both he and the crates fly out through the opening and disappear into the Time Vortex itself.
The TARDIS doors close and the atmosphere inside the control room returns to normal. Alice demands to know where Mulberry has gone, but the Doctor says he could be anywhere or he could be dead. He checks the controls and realises the ship is now going up the time corridor again, back towards the Daleks. In fact, they're moving behind the crates, which are still intact and moving through the corridor ahead of them. They're now on a direct collision course with the nano-Daleks being fed down the time track to invade the Earth.
On the new Dalek homeworld, the Daleks realise their particle forces are converging on the same spatio-temporal courses in the time corridor. The Doctor has tricked them -- when the two nano-Dalek forces meet they will be mutually destroyed. Seconds later, the TARDIS materialises before them. The Daleks order them to surrender, but the Doctor ignores them and asks the Greylish if he's given any thought to his earlier conundrum. The Greylish confirms that the Doctor's words have been echoing inside his head -- the Daleks have always been here, yet this has always been his domain. The Greylish has realised that he is the seed Dalek, the one that was replicated to make the nano-Daleks. A creature entirely indifferent to the evil that Daleks do, who saw himself as impartial, but whom the Doctor regards as just another Dalek, no different to the rest of them. The Greylish disputes this and says that only part of him is organic -- the seed for the nano-Daleks. He now realises he is also a construct, sustained by the Daleks' structured mind-share. He was created by the power of the Daleks' thoughts and in turn, he willed this place, the Pan-Temporal Ambience, into existence. He now knows he has the power to stop the Daleks, but the Daleks turn on him and insist that he was created simply to obey them and provide the seed for their new conquest of Earth. The Greylish tells them it will only take a single thought to transgress this place back to the dimensional nullity for which it was originally created.
The Doctor thanks the Greylish, who in turn bids everyone goodbye. The Daleks declare an emergency as the Greylish starts to enter the dimensional nullity, but there's nothing they can do to stop their world from being destroyed and themselves along with it. The world created by the Greylish collapses in on itself and after a few seconds, it ceases to ever have existed.
Inside the TARDIS, Nyssa tells the Doctor that the Daleks' time corridor has evaporated and they seem to be drifting back towards Earth again. Then she realises Wilton is no longer with them. First Mulberry, then the Greylish and now Wilton. Why is it that defeating the Daleks always costs the lives of innocents? The Doctor sadly explains that Wilton's disappearance is a sign of their "victory". Now that the timeline has corrected itself, the Dalek occupation of 2158 existed in the way that it always did and Wilton no longer exists. The Doctor can't even be sure whether he or General Tillington were ever born or whether they died during the invasion. It doesn't seem like much of an achievement to the Doctor, but Nyssa reminds him that at least this way they know the Daleks on Earth will ultimately be defeated. Floyd and Major Alice Hunniford are still a bona fide part of Earth's history, and that's exactly where they belong. The Doctor starts to programme the TARDIS to return them to where he found them, but Alice starts to protest. The Doctor isn't surprised and he imagines she'll have plenty to say along the way...
|Source: Lee Rogers|
In Winter for the Adept
, Nyssa was separated from the Doctor when one of their experiments apparently went wrong; however, in that case it was the Doctor's experiment that was responsible.
The Zero Room was destroyed in Castrovalva
, but the ship has obviously grown a new one since then. The HADS was introduced in The Krotons
The Doctor would appear to have perfected the technology of the pocket interocitor by The End Of The World
, as he upgrades Rose phone to allow her to call home across time and space.