The time is out of joint. The Daleks have deployed a temporal extinction device within a time fissure, relying on their pilot to maintain their vessel’s stability within the Time Vortex. However, when the device is detonated, the time fissure becomes unstable, and the Dalek time ship is swamped by a tidal wave of temporal energy. With only a few seconds left, the Daleks open a time corridor, link it to one end of the time fissure, and send out three strategists and their pilot. One of the strategists is caught in the collapsing tunnel and is destroyed, but the others escape to safety while the remaining Daleks await rescue. “And thus the whirligig of Time brings in his revenges...”

The Doctor and Charley ride out a tidal wave of temporal energy caused by some vast disturbance in the Time Vortex. The Doctor makes what he considers to be some clever jokes alluding to Shakespearian quotes while searching for the cause, but Charley doesn’t have the faintest idea what he’s talking about. The Doctor is bewildered, especially when he finds that Charley knows of Ben Jonson and Christopher Marlowe -- and yet has never heard of William Shakespeare. It now occurs to him that Orson Welles failed to recognise a Shakespearian quote as well -- and when his work is complete he discovers that there is a time fissure stretching from the mid-21st century back to the sixteenth. Something is going to cause William Shakespeare to vanish from history -- but right now this is just a possibility rather than a fact, and the Doctor still has a chance to restore Shakespeare to the timeline before it becomes a certainty.

At the future end of the time fissure, Britain is a benevolent dictatorship ruled by General Mariah Learman -- who has once again refused to call elections. Learman’s niece Viola listens in despair to her broadcast, as does her young servant, a confused kitchen boy; Major Ferdinand may believe that Learman would be seen as giving in if she steps down now, but Viola wants her aunt to give up power gracefully. Learman finishes her broadcast with an apt quotation from Richard II -- which, as the young boy points out, is ironically about a ruler who is deposed. Elsewhere, the rebels Priestly and Hart listen to the broadcast, and, infuriated by Learman’s unconstitutional act, they vow to restore the democracy -- and Shakespeare.

The TARDIS materialises in Learman’s palace, the seat of New Britain after the Euro Wars. The Doctor and Charley emerge and run into Major Ferdinand, who mistakes the Doctor for the public relations expert who is expected to help Learman smooth over her deferral of elections. The Doctor plays along with the mistake, and arranges for the real PR man to be turned away when he arrives. Learman explains that the rebels aren’t widely supported; they are only causing trouble because people have begun to forget the existence of Shakespeare, and the rebels seem to be under the impression that Learman is somehow responsible. Learman takes the Doctor to the library to speak with Viola, and dismisses the boy back to the kitchen while his betters speak. Viola agrees with the rebels’ claim that Shakespeare has been removed from history altogether, although Learman apparently believes that his loss from public memory is the result of some form of mass hysteria. The Doctor suggests that the event which erases Shakespeare from history may not have happened yet -- it’s only a possibility which is slowly becoming more probable, which is why some people still remember him. He is surprised when Learman doesn’t dismiss this claim out of hand, and she admits that the rebels blame her for Shakespeare’s loss because she’s been experimenting with time travel herself...

Elsewhere, the rebels lose another of their band when she fails to recognise any Shakespearian quotations. Hart wonders whether Learman is experimenting with time travel in order to save Shakespeare, but Priestly scoffs and reminds him of their rallying cry -- “Free Will”. It’s hard for Hart to think about the subject clearly -- especially at night, when the nightmares come. Viola then contacts them, and once again tries to persuade them not to do anything rash. She still hopes to persuade her aunt to step down of her own free will, especially now that this strange Doctor has arrived. The rebels agree to hold off attacking Learman openly for the moment, and to give Viola a chance to end things peacefully.

Learman takes the Doctor and Charley to a hall of clocks and mirrors, where Professor Osric is working on the master clock, the key to Learman’s time machine. There are over 1600 clocks in the hall, and 100 mirrors coated with orthopositronium, a substance in which the electron and positron orbit each other in the same direction. Since light takes time to travel to and from a mirror, the image in any mirror is in fact an image of the past -- albeit the very recent past. The orthopositronium enables Osric, at least in theory, to open a portal into the mirror image. The clocks apply Heisenberg’s Uncertainty Principle to the very structure of Time; the act of measuring Time changes it, and with the master clock, Osric can theoretically tune the mirrors into any event in the past.

Unfortunately, while the theory holds, Osric is having trouble getting the machine to work in practice, as he lacks a source of chronons to power it. However, he claims that the machine has in fact worked once; nearly a month ago the mirrors opened briefly, and help arrived. The Doctor finds this disturbingly familiar, and when Osric’s new assistants enter the hall of mirrors, the Doctor has had at least a moment to prepare himself to face the Daleks. These Daleks claim to venerate Shakespeare, the greatest playwright in the Universe, a claim which the Doctor finds utterly unbelievable. Nevertheless, with the Daleks’ help, it seems Osric has finally recharged his master clock, as the chronon level is now increasing and will soon reach optimum levels. Within an hour, Learman will be able to watch the premiere performance of Julius Caesar live -- and she refuses to listen to the Doctor’s claims that the Daleks are bound to have their own agenda.

Disturbed, the Doctor heads for the library to think things over, leaving Charley in the hall of mirrors to keep an eye on Learman and Osric. On his way, he encounters Viola, who asks him to help convince her aunt to abandon her futile obsession with Shakespeare and concentrate on putting the country to rights. Viola fears that they’re heading into the future everyone is seeing in their nightmares -- a future of conformity and oppression, a nightmare world in which the human race is just a faceless mass of non-individuals blindly following orders. The Doctor knows that the nightmare will become real unless he can stop the Daleks, and retreats to the library, where the kitchen boy is reading some of the books. He also finds a Dalek, who warns the Doctor not to interfere. As the Dalek departs, the Doctor falls into a fugue, staring into space and losing the time he needs to conduct research. This may be a result of the temporal anomalies, which are growing worse as the possibility of Shakespeare’s loss becomes ever more probable. When the Doctor and the kitchen boy look at the First Folio which Learman had been displaying earlier, they find that all of the pages are blank. It may be too late already...

Despite the Doctor’s warnings, Learman welcomes the new arrivals, who despatch security squads to ensure that nobody interferes with their work. They still claim that they intend to rescue Shakespeare, however, and the Doctor realises that Learman must have something else they need. She admits, to Osric’s surprise, that she already knew the Daleks’ ship was stranded in the Time Vortex and that she offered her facilities to help them repair it. The Doctor doesn’t trust the Daleks for one minute, but nevertheless agrees to help them while he tries to figure out what they’re up to. Ferdinand is vexed by the new security arrangements, as the Daleks won’t let him near the barracks -- and he’s beginning to suspect that Learman isn’t telling him the whole truth. He is right to be concerned; the Daleks have already exterminated all of the “extraneous” human guards, and on their ship, they’re preparing another temporal extinction device, which they intend to power via the palace’s nuclear reactor. They have detected a chronon source in the hall of mirrors, presumably the master clock, which will serve as a new temporal stabiliser; once they have that, they can resume their conquest of Time.

The Doctor, Charley and Viola retreat to the library to examine the blank Folio, and Viola is upset to learn that the kitchen boy had been reading it earlier -- although she disagrees with her aunt’s belief that the works of Shakespeare are too good for the likes of him. She also distrusts the Daleks, however, and leaves the library, convincing the Dalek on guard that she has been summoned by General Learman. The Doctor decides to start converting the master clock into a workable temporal stabiliser, intending to draw out the work and delay the Daleks until he learns their real intentions -- as it is, he isn’t even sure why the master clock seems to work. He and Charley set off back to the hall of mirrors, and the Doctor quotes Shakespeare as he goes. The Dalek recognises the quote and matches it: “Blood will have blood.”

Viola contacts Priestly to warn him of the change in circumstances, but the Daleks trace the transmission, blast open the door, destroy the communicator and take Viola prisoner. Priestly hears the gunfire and then silence, and, unsure what’s happening, tells Hart that it’s time to attack. The rebels storm the palace, to Viola’s horror -- they don’t know what the Daleks can do. They soon find out. In the confusion, Viola gets away from her guard and flees, but she refuses to escape with the rebels, knowing that the Daleks will hunt her down and exterminate the others. She orders Priestly and Hart to get to safety, while she steals the master clock from the hall of mirrors. Priestly reluctantly obeys, but Ferdinand catches them escaping; however, he knows that they now face a common enemy, and thus shows them another way out while he lags behind to delay the pursuing Daleks.

The Doctor and Charley hear the gunfire, but their guard refuses to let them investigate and herds them back to the hall of mirrors. There, Osric is surprised when Viola bursts in, grabs the master clock, and orders the pursuing Daleks to back down or see it destroyed. When the Doctor and Charley arrive the Daleks try to use them as hostages, but Viola calls their bluff; they still need the Doctor’s and Osric’s help, and if they kill Charley the Doctor will refuse to help them. At that moment, the kitchen boy arrives, confused and seeking Viola. Rather than let the Daleks use him as a hostage, Viola resets the time on the master clock, and a different era appears in the mirrors. Charley tries to intervene, but a time portal opens up and she falls through with Viola, ending up in an entirely different time zone.

Viola, still carrying the master clock, tells Charley to follow her, and Charley realises that Viola knows where she’s going; she has been here before. It’s September 19, 1572, and there is another mirror about half a mile away, linked to a small building in the palace grounds -- where the rebels have been hiding under Ferdinand’s nose. Viola has been keeping them at bay while trying to persuade her aunt to see reason. But this doesn’t explain why the rebels have their own time mirror, and before Viola can explain, she and Charley see something terrible -- a patrol of Daleks herding slaves along the road, exterminating those who are too weak to keep up. Charley finally understands what the Doctor was talking about earlier; history has been changed, and the people of New Britain have been having nightmares of the alternate timeline which is superseding their own. In this version of history the Daleks have always been the masters of Earth. The Daleks spot Viola and Charley hiding nearby, and pursue them, believing them to be escaped slaves. The women flee for the mirror, their only way out of this time.

The Doctor is surprised to learn that Viola has transported herself to the significant date of 1572. This seems to prove that the master clock works, and since it is now stuck in another time zone the Daleks can no longer use the hall of mirrors to open time portals. The Doctor, however, believes that he can cobble together a short-term stabiliser, and the Daleks thus lock him in Major Ferdinand’s office to work. Ferdinand is also there; he’s too prominent a figure for the Daleks to exterminate as yet, but they suspect that he helped the rebels to escape and have thus locked him up. His office has a mirror, but he can’t use it to escape -- at least not until the Doctor jury-rigs a device which opens a link between this mirror and the time portals in the hall of mirrors; he has no need of a temporal stabiliser to do so, since he is only moving through space, not time. He and Ferdinand step through the mirror and escape -- but are surprised to find that their destination is not the hall of mirrors after all...

Meanwhile, Learman and the Dalek Supreme discuss their arrangement. For now, their interests coincide, and Viola will simply have to take responsibility for her own actions. The master clock is currently in the Elizabethan time zone, but the Daleks are confident that they can recover it. And then they can deal with Shakespeare as they promised Learman they would.

Much to Ferdinand’s surprise, he and the Doctor have emerged from the mirror in the rebel camp, and the rebels’ mirror is already tuned to 1572. It has only worked properly once, about a month ago, but now the mists are clearing again to reveal Viola on the other side. Charley is keeping watch at the door as Viola tries to open a time portal, but the master clock doesn’t seem to be working. The Doctor decides to return to the hall with Ferdinand and open a portal from there -- but when he hears Charley warning Viola about approaching Daleks, he realises that history is already altering for the worse. He and Ferdinand open up a spatial portal to the hall of mirrors, surprising Osric and the kitchen boy with their arrival. Osric admits that he and Viola set up the rebels’ time mirror, but there’s no time to explain why, as the Doctor sends him through to the rebel camp to help rescue Charley and Viola. Once this is done the rebels must attack the Daleks before they have a chance to alter history. Unfortunately, moments after Osric departs, Learman and the Dalek Supreme arrive, searching for him -- and despite Ferdinand’s attempts to distract them, the Dalek Supreme sees the rebel camp through the mirror portal and realises that they are being betrayed.

Osric can’t generate a time portal without a chronon source, and Charley and Viola are about to be discovered. Charley rushes to Viola’s side as the Daleks enter the house -- and just as the Daleks are about to open fire, the mirror opens up and Charley and Viola are transported to safety. As they watch, the Daleks in the Elizabethan time zone vanish, replaced by suspicious human soldiers; the probabilities have changed again, and the rebels are more likely to win. Priestly and Hart decide to pass through the portal into the hall of mirrors, attacking the palace from within and taking the Daleks by surprise. Unfortunately, when Osric steps back through the mirror he finds that Learman and the Dalek Supreme have seen everything. The Dalek Supreme exterminates Osric and summons more Daleks to ambush the rebels when they emerge...

Fortunately, the master clock absorbs most of the blast, and Charley is only stunned. The surviving rebels retreat into the palace corridors, and Priestly, shocked by the loss of so many of his men, is even more shocked when he mentions Shakespeare and Hart has no idea what he’s talking about. As far as Hart remembers, Learman is a puppet ruler and the Daleks have been the masters of Earth since the dawn of time. Priestly realises that the Doctor was right; history is crystallising on a new and brutal path, and the only way to stop the Daleks now is via the palace’s nuclear reactor.

Learman prevents Viola from following the rebels, and checks to see whether the master clock is undamaged, regarding it as much more important than Charley. The Daleks take Charley prisoner to ensure the Doctor’s continued co-operation, and allow Viola and the kitchen boy to look after her. The Daleks then put the master clock back in place, but the time portals fail to open; presumably the clock was damaged by the blast after all. The Dalek Supreme returns to its ship to report, ordering the Doctor to repair the clock; however, the Doctor still doesn’t understand how the clock worked in the first place without generating a chronon source. In order to delay the Daleks, the Doctor insists that he and Ferdinand be allowed to speak with Charley once again, claiming that she has vital information. Meanwhile, the Dalek Supreme reports its progress to the Emperor. Their victory over Time seems assured...

The Doctor and Ferdinand dismiss their guard and speak privately with Charley and Viola. They must help the rebels, but to do so they must get out of this room, and the Daleks have smashed the mirrors. The Doctor therefore sends the kitchen boy to fetch some lunch for him, with very specific instructions on what to do with it. Despite his nervousness, the boy agrees to do so, and the Daleks allow him to fetch food from the kitchen... food wrapped in silver foil. The Doctor builds another device to transform a mirror into a spatial portal, and the others unwrap their food and spread the reflective foil on the floor, creating a flat mirror. The Daleks detect the portal’s activation, however, and although Viola and Ferdinand manage to escape, the Daleks enter the room before the Doctor can send Charley and the boy after them. The Daleks order the Doctor and Charley to follow them to their ship, while the boy remains a hostage.

Priestly, Hart and the other rebels arrive at the palace reactor, only to find it swarming with Daleks who are preparing to siphon its power to their ship. Rather than simply shutting down the reactor, Priestly therefore decides to blow it up. Hart knows the Daleks’ weaknesses; in his version of history, he’s been fighting them for years. Perhaps they will be able to stop the Daleks before history is changed permanently. Viola and Ferdinand arrive, having stopped off at the armoury; they’ve seen the Daleks taking Learman to their ship but are unsure why. Ferdinand convinces Priestly to stage a decoy attack with half his men, and to take the rest around the back -- and use plastique to blow a hole in the wall, getting behind the Dalek lines and reaching the reactor.

The Doctor and Charley are brought before the Dalek Supreme, who has summoned them to deliver an ultimatum; if the Doctor does not repair the master clock within an hour, all humans within the palace will be exterminated. As the Doctor and Charley depart, Learman enters, and the Doctor, curious, decides to find out what she and the Dalek Supreme have to discuss. Rather than returning to the hall of mirrors, he and Charley enter the portal, wait for their guard to leave, and then re-emerge on the Dalek ship without having to risk opening another portal and alerting the Daleks. They soon locate a computer bank with a video feed, and watch as Learman discusses the operation’s progress with the Dalek Supreme -- thus revealing her true agenda. Learman believes that Shakespeare’s genius transcends the ability of the rabble to understand it -- that the people of Britain simply treat him as a figurehead of their country’s success, resting on their laurels without appreciating his true genius. She doesn’t want the Daleks to rescue Shakespeare, she wants them to kill him. Before doing so, they will provide her with a temporally shielded copy of the complete works of Shakespeare -- and thus, she will be the only person in the entire Universe ever to know that he existed.

Now that he knows what Learman is really up to, the Doctor needs to know the same about the Daleks. He manages to access the ship’s flight recorder, and he and Charley watch the events which led the Daleks here. The Doctor learns quite a bit. The time fissure was already there before the Daleks began to tamper with it, and there’s actually an entire fleet of time ships trapped in the Vortex rather than just this one. When their ship was endangered, the Daleks opened an escape corridor, attached to one end of the time fissure -- Learman’s mirrors -- and sent their pilot and three strategists to organise a rescue attempt. One of the strategists was killed when the escape corridor collapsed, and the two survivors, as the Doctor and Charley have seen, made a deal with Learman and used her mirrors to open a portal back to their ship, stabilising it within the Vortex. But what happened to the pilot? And what is the “device” which the Daleks were using in the time fissure?

Hart leads the decoy attack at the reactor while Ferdinand, Viola and Priestly blow open the wall. The Daleks quickly recover from the surprise, however, and Hart is exterminated while trying to join the others. Most of the other rebels are killed as well, but Ferdinand, Viola and Priestly seal themselves behind the radiation shield in the main reactor. As the Daleks attempt to blast their way through, the three allies set to work on their suicide mission -- to sabotage the reactor and blow the palace sky-high.

The Doctor and Charley return to the hall of mirrors to ponder what they’ve learned, but the Daleks detect the opening portal -- and also detect a chronon source in the hall of mirrors, apparent proof that the Doctor has repaired the master clock. Learman and the Dalek Supreme confront the Doctor, and use the master clock to tune the mirrors in the hall to different eras in the past -- Roman times, Regency Britain, the Great Plague, the Blitz... And all of the eras are changing, becoming infested with Daleks. The possibility of Dalek victory is becoming more certain. As a pair of Daleks prepare to enter the mirrors and assassinate Shakespeare, Learman explains to the Doctor that humanity is decadent, and the Daleks are bound to win anyway; her way at least the memory of Shakespeare will survive.

With only seconds to go before the reactor explodes, Daleks pils up against the bulkheads and activate their self-destruct mechanisms, blasting open the shutters -- and cracking the reactor core seals. More Daleks enter the reactor and shut it down, exterminating Priestly when he tries to stop them. The seals crack, but Ferdinand and Viola escape moments before the Daleks lower the secondary blast shutters. The reactor will not explode -- but the Daleks trapped within the irradiated area will never be able to leave.

Learman leaves the hall of mirrors, satisfied that all is going well -- but one of Charley’s offhand remarks gives the Doctor an idea, and he resets the time on the master clock. She is still holding it, but since it’s linked to the mirrors, she’s safe; otherwise she would have travelled back in time a few seconds, met her younger self, and been obliterated by the energy discharge. As it is, the Doctor has merely relocated the time portals’ destinations. Instead of arriving in the Elizabethan era, one Dalek materialises during the Blitz and is destroyed by British soldiers; the other is killed by Roman soldiers evacuating from a very familiar fort. The Dalek Supreme insists that this is merely a delay, and informs the Doctor that the Daleks have acquired their knowledge of time travel from the Time Lords, using the data acquired from the invasion of Gallifrey and their study of the Kar-Charrat time barrier. The Doctor chooses not to reveal how worried he is when he learns that the Dalek Emperor is on board one of the vessels in the time fleet -- which shows just how confident the Emperor must be. The nuclear reactor was only a sideshow after all, which means that the Daleks must have some other way to crack open the time fissure.

The Dalek Supreme returns to his ship and reports to the Emperor that all is prepared. Another temporal extinction device is ready, and the master clock is fully functional. They need only a pilot to replace the one destroyed when they arrived at Learman’s palace -- and though the Doctor is too unreliable to serve as one, the Supreme has another candidate in mind.

The Doctor realises that the Daleks must have tried to detonate a bomb within the time fissure to split it open, and that their attempt failed and left them trapped in the Vortex. Trying to learn more, the Doctor resets the mirrors to observe the past, and he and watch the pilot and the two strategists’ arrival in the hall of mirrors. Shocked, Learman quotes from Shakespeare as always -- and the Daleks recognise the quote and match it in kind, thus convincing Learman that they too are Shakespearian scholars. Learman steps forward to shake hands, as it were, but when she touches the pilot it disintegrates in a blast of temporal energy so powerful that it even shorts out the Doctor’s mirror as he watches. The Doctor theorises that the Daleks were charged with chronons due to their journey through the time corridor, and that by touching the pilot, Learman grounded it to the present. Or perhaps there’s another explanation... In any case, it means that the Daleks now need another pilot.

The Daleks burst into Learman’s study and reveal that they intend to transform her into their new pilot. She already has the necessary temporal expertise, and the specific knowledge of the Daleks’ equipment will be provided by the positronic links between her casing and the control systems. They will, however, stick to the letter of the agreement, if not the spirit, and attach a memory sphere containing the complete works of Shakespeare to her positronic links. The Daleks force the protesting Learman to the reactor, where they have established a temporary time corridor to accelerate the effects of drugs and radiation on her body. Learman is thrust into the corridor, vowing to be revenged on the whole lot of them. As she begins to mutate into a Dalek, the Dalek Supreme turns to the leader of the scientific division whose failure to protect the reactor endangered the palace, and orders it to surrender its casing for the new Dalek. The squad commander is thus forced to disconnect itself from its life support systems, though this means its death. When the Dalek mutant that was once Learman emerges from the time corridor it is placed in its new casing, complete with memory sphere. “Ill met by moonlight!”

The Doctor is disturbed by the number of temporal paradoxes he’s encountered recently, and he still doesn’t know what first created the time fissure or how Shakespeare fits into all of this. When Charley tells him that the rebels’ mirror was already tuned to 1572, however, he realises the truth, and takes her to the library. There, the kitchen boy is waiting for them -- and although he’s been told not to tell anyone the truth, the Doctor has already guessed for himself that the young boy is named Will. The Doctor now knows that the master clock has never worked as a chronon source; the first time the mirrors functioned this was due to residual energy bleeding through the fissure from the Daleks’ temporal extinction device. The same residual energy enabled Viola to travel back through Time via the rebels’ mirror and “rescue” the young Shakespeare before anyone else could get to him -- thus removing him from Time in the first place, causing the event she was trying to prevent, and creating the paradox which cracked open the time fissure in the first place.

The Daleks summon all remaining humans -- the Doctor, Charley, Viola, Ferdinand and young Will -- to the hall of mirrors to witness their triumph over Time. They still believe the master clock to be the chronon source which will stabilise their vessel, and their temporal extinction device is fully charged. As the Daleks’ new pilot sets off for their ship it quotes from Shakespeare, and the Doctor realises that it used to be Learman; all the pieces of the puzzle are falling into place. He thinks that all he has to do is wait, but the Dalek Supreme informs the Doctor that it has his TARDIS on board its ship, and to ensure that he does not interfere it takes Charley hostage as well. This is the worst thing that could have happened. Charley is forced to enter the time portal and is taken to the bridge of the Dalek time ship, where the Daleks place the master clock in position. Chronon levels within the bridge begin to rise, and the Dalek Supreme, satisfied, closes the time corridor, severing the link to the palace...

The Doctor is deeply concerned, not just for Charley’s sake, but because her presence could prove key to the Daleks’ victory. He can still establish a link to the Daleks’ ship as long as it remains stable within the Vortex, but first he must deal with the two Dalek guards in the hall of mirrors. Fortuantely, Ferdinand still has one grenade left. The Doctor distracts one of the Dalek guards, leaping about until the angry Dalek tries to exterminate him; however, he has calculated the angles precisely, and the blast reflects from several mirrors and destroys the second Dalek. Ferdinand then attacks the remaining Dalek, but finds that he can’t lodge the grenade in place -- and thus gives his life to hold onto the grenade and the Dalek at the same time, ensuring its destruction.

The Doctor opens a time portal into the Dalek timeship, and he and Viola enter -- followed by young Will, who is terrified but determined to help his friends. Viola thinks that the Doctor intends to steal the master clock, but he claims that it’s not important. Learman’s mirrors only worked the first time because of residual energy from the temporal extinction device’s detonation, and on every other occasion that the mirrors worked properly -- when the Dalek strategists opened the first portal back to their ship, and when Viola travelled to the 17th century and back -- something else was present. Something which the Daleks now have on board their ship...

The Dalek Supreme, satisfied that victory is inevitable, orders that Charley be taken away to await extermination. As her Dalek guard forces her through the ship’s corridors, however, the Doctor locates her, creates a distraction, and manoeuvres her guard out through a time portal into the Vortex, where it is destroyed. The Doctor and his friends then retreat to the TARDIS, which the Daleks have indeed taken aboard their ship, and depart. Satisfied, the Doctor tunes the scanner to the same frequency as the Dalek ship’s monitors to watch their defeat, for he now knows why the pilot disintegrated when it touched Learman. The Daleks will now attempt to use the master clock as a temporal stabiliser -- and it will do them no good. The real source of chronon energy is, and always has been, Charley.

“Time has come ’round, and where I did begin, there shall I end.” The Daleks deploy their temporal extinction device within the time fissure, relying on their pilot to maintain their vessel’s stability within the Time Vortex. However, when the device is detonated, the time fissure becomes unstable, and the Dalek time ship is swamped by a tidal wave of temporal energy. With only a few seconds left, the Daleks open a time corridor, link it to one end of the time fissure, and send out three strategists and their pilot. One of the strategists is caught in the collapsing tunnel and is destroyed, but the others escape to safety while the remaining Daleks await rescue. “And thus the whirligig of Time brings in his revenges...”