Hunters of Earth ( audio story ) Publisher ' s summary . Shoreditch , London , 1963 . The Beatles have beaten John Smith and the Common Men to No . 1 and satellite s are being launched in outer space . Back down on Earth , strange goings - on are occurring : the normally placid teenagers of Coal Hill are running riot and a master thief is stealing highly specialised equipment . Schoolgirl Susan Foreman just wants an easy life for herself and her grandfather , the mysterious Doctor . She wants to be liked and accepted by Cedric and all the other pupils at Coal Hill School . But there ' s trouble in the streets and bombsites around Totter ' s Lane . The teenagers are becoming dangerous . . . Their mission : to hunt down anyone different , or alien . . . Susan ' s quiet life is about to spiral out of control . Having inadvertently started drawing attention to herself , she finds herself drawn into a desperate situation . Suddenly , the chase is on and she and her grandfather are now the hunted . Plot . In London ' s East End , during a foggy Thursday night of October in 1963 , the First Doctor is hurrying down a street , clutching an item that will help him repair the TARDIS . Two motorbikes , being ridden by teenagers , come right at him , but the Doctor quickly gets out of the way . He then notices that someone is following him . He hurries down the street , only to stop when a figure appears from the fog , ahead of him . The figure turns out to be Susan Foreman , the Doctor ' s granddaughter . Susan says that she has been looking for him . She notices the item the Doctor is carrying and accuses him of stealing it . The Doctor admits to such , pointing out that they need it to repair the TARDIS . Susan tries to get him to promise her to get any future components legally , like everyone else . The Doctor is against it , not wanting to draw any unwanted attention to him and Susan . However , he promises her that he will do so . The Doctor notices a figure nearby , heading for them . The two quickly leave and enter the junkyard where the TARDIS is . As the Doctor tries to locate his TARDIS key , Susan looks through a hole in the wall . She watches the figure approach the junkyard and can make out his features . The man pauses in front of the gate , before shaking his head and walking on . The Doctor finds the key and opens the door , allowing the two to enter the TARDIS . Susan tells the Doctor that she recognises the man as Colonel Rook , a teacher at Coal Hill School . The next day , after school , Susan is all alone , as she ' s not good at being social with humans . She pulls out her transistor radio and turns it on . She is so absorbed in the music that she doesn ' t see Colonel Rook until she bumps into him , causing him to drop some papers . Susan apologises and helps Colonel Rook pick up the papers . Colonel Rook glares at Susan ' s radio , making Susan realise that he wants it to be turned off , so she does so . Rook gives Susan an odd stare , creeping her out . He asks her how long she ' s been a pupil at Coal Hill . He then points out that he had talked to the secretary , who has no recollection of receiving any documentation on Susan , not even a birth certificate . Susan tells him that her grandfather and her have been travelling , and the documents had been sent to them , but must have gotten lost after that . Colonel Rook then mentions how odd of a student she is , how " unearthly " she is . Susan uses the excuse of homework to end the conversation , so Colonel Rook leaves . Cedric , another student at Coal Hill , walks up to Susan , having overheard the conversation . He invites Susan to join him and his friends at Rosa ' s . The two head for Rosa ' s , listening to Susan ' s radio . Neither notice Colonel Rook watching them leave . At Rosa ' s coffee bar , Susan and Cedric join the rest of their friends . They are joined by Rosa , the owner . Rosa is a refugee from another country , that was bombed due to the war . However , her adjusting to living in Coal Hill hasn ' t gone smoothly , as she has been harassed by people . The trouble started four months ago , around the time Susan and the Doctor first arrived . As Rosa returns to work , one of Susan ' s friends , Mavis , asks her to change the music . Rosa changes the radio station . Suddenly , Susan lets out a yelp of pain , as she is suddenly struck with a headache . As Cedric heads off to get some water for Susan , the music on the radio gets cut off . Cedric comes back with the water , and suddenly Mavis smacks it out of his hand . She starts saying that people like Susan should go back where they came from . She then grabs a knife and moves to attack Susan , but Brian and Richard , the other two who were with them , try to restrain her , but she shakes them off . She starts circling Susan and Cedric , who was defending Susan . Rosa comes over , turning off the radio as she demands to know what is going on . Mavis suddenly returns to normal , confused on what had happened . Mavis feels a headache hit her and has no memory of attempting to harm Susan . Brian and Richard escort Mavis home , while Cedric asks Susan if she ' s okay . Susan is fine , and her headache is gone . Rosa comes over and cleans up the broken glass and dropped knife . Rosa feels sympathetic towards Susan , as the words Mavis had said to Susan were the same kind of words said to Rosa by those who had harassed her . Susan turns on her radio , just as the Doctor enters . He informs her that he will be taking care of some business , so he won ' t be around when she goes back to the TARDIS . Cedric asks him about what he ' s talking about , but the Doctor doesn ' t answer , instead asking Susan who Cedric is . She introduces him . The radio cuts out again . Susan tries to adjust the radio to get any music , but has no success . Just as she ' s about to turn it off , the static clears and the DJ starts talking , passing on a cryptic message to Susan and Cedric , from a future incarnation of the Doctor . Susan shuts off the radio as soon as the message is finished . The Doctor has no idea what his future self is talking about , but is worried nonetheless . Cedric is confused , but Susan refuses to explain . Cedric tries to protest , proclaiming that as part of the message was meant for him , he should get an explanation . The Doctor disagrees and then tells Susan to head back to the TARDIS . Cedric offers to walk Susan home , but the Doctor is against it . Susan leaves the cafe , the Doctor following a few seconds later . The Doctor makes his way to Magpie Electricals , to purchase parts needed to repair the TARDIS . He hands the owner , Bernie , a list of components he needs . Bernie asks the Doctor what he needs the items for , but the Doctor refuses to tell him . The Doctor asks him if he will be able to get all the components on the list . Bernie tells him that he will have them by Tuesday afternoon . He asks the Doctor to give him an address to send the components to , but the Doctor proclaims that he will pick them up himself . Bernie asks for the Doctor ' s address again , this time so he will know where to send the bill . The Doctor writes the address down . Bernie gives the Doctor a card with the address of the warehouse where the parts will be . The Doctor leaves . Unknown to him , Colonel Rook was also in the shop , hidden and listening in . Bernie hands Rook the paper that the Doctor wrote his address on , confirming Rook ' s suspicions that the Doctor really was using the junkyard . That leaves only one question . What could the Doctor be hiding in the junkyard ? Rook then gives Bernie some instructions to carry out . The Doctor is hurrying along the darkened streets , pleased that he will get the components he needs , and that he did so while keeping his promise to Susan . He had been lucky to find out about the shop , having noticed the advertisement in the morning newspaper . Suddenly , five teenagers in leather jackets appear , blocking the way . The Doctor demands that they get out of his way , but they just sneer at him instead . They ask him what he thinks he ' ll do to them if they don ' t move . They start moving closer to the Doctor , surrounding him . The Doctor demands again that they let him go . The leader of the five , Jimmy , mocks the Doctor . He asks the Doctor why he would be around the East End . Jimmy grabs the Doctor and proclaims that they don ' t like people like the Doctor around here . He tells the Doctor to go back to his own kind . The Doctor asks what will happen if he doesn ' t . Jimmy pulls out a knife and presses it against the Doctor ' s throat . Meanwhile , Susan has just arrived at Totter ' s Lane . As she approaches the junkyard , she notices that the door is slightly open . Thinking that her grandfather had changed his mind and come back , she enters the junkyard . Someone had been searching for something in the junkyard , as a lot of objects have been moved and overturned . Susan instinctively runs over to the TARDIS and lets out a sigh of relief , as the TARDIS was left untouched . Susan looks over at the far wall of the junkyard and notices that two words have been painted on , " Aliens out ! " The junkyard ' s gate is opened again . This time , it ' s the Doctor . Susan runs over and hugs him , happy to see him . The Doctor tells her about the gang that had attacked him , and then suddenly stopped . They apologised to the Doctor for attacking him , and offered to transport the Doctor back to Totter ' s Lane . Susan draws the Doctor ' s attention to the graffiti on the wall . To the Doctor , the words can only mean one thing . Someone knows who the Doctor and Susan are . This means it is now more imperative that they finish the repairs to the TARDIS , so they can depart . The next day , Susan is waiting for Cedric at the corner of what used to be Mayfield Terrace . It had been destroyed by the war . Nowadays , the students of Coal Hill would mess around in its remains . Susan is listening to her transistor radio . Cedric arrives , and apologises for being late . The two decide to take a shortcut across the bomb site to get to their destination . The radio cuts out and Susan feels another headache hit her . Suddenly , bricks are being thrown at them by a group of twenty teenagers . Susan recognises some of them as students from Coal Hill . Mavis is the one leading the group , and she is holding an iron crowbar . Mavis yells at Susan , telling her to leave , and proclaims that they don ' t want any aliens here . Susan and Cedric try to run , only to find their path blocked by Jimmy and his gang . Susan ' s headache is overwhelming her . She then notices that Cedric is no longer helping her . He has suddenly joined the group attacking her , proclaiming that no aliens should be here . Susan begs for them to stop , but they don ' t listen . Susan tries to escape , but fails . Mavis grabs her and moves to hit her with the crowbar . In the struggle , Susan ' s radio falls from her pocket , and shuts off . Suddenly , everyone returns to normal , confused on what they were doing there . The group breaks up , heading off without saying anything . Cedric picks up Susan ' s radio and hands it back to her . Susan instinctively backs away from him . She tells him that he had joined the others in attacking her . Susan notices her headache is gone . She is certain now that something is affecting people , turning them violent . But for them to suddenly stop makes no sense . Cedric asks her why the group had called her an alien . A few days later , Susan thinks back to the evening when she had discovered the graffiti . The Doctor had told her to be extra careful . On Tuesday , he will get the remaining parts he needs to finish the repairs to the TARDIS . Once the repairs are complete , the two will depart . The thought of leaving had been plaguing Susan ' s mind all day , as she sits with Cedric after buying a Bob Dylan record . She confides in him about her grandfather planning on them leaving , and that she doesn ' t want to leave . Cedric mentions that his uncle is in the army . He asks her why she doesn ' t go to the authorities about the attack on her . Susan says that her grandfather would not like that . Susan thanks Cedric for being her friend . Cedric turns his attention to the music they had bought , and asks Susan why she had him buy it . Susan tells him it was because of the mystery message from the radio . She tells him to listen to the lyrics , for they might make him think . Meanwhile , the Doctor heads for the warehouse , to pick up the parts he ordered . When he arrives , Bernie meets him there . However , Bernie looks different than before . He opens the gate to the warehouse and asks the Doctor to come inside . The Doctor is suspicious , but still enters the warehouse . Once inside , Bernie shuts the gate and locks it , trapping the Doctor inside . The Doctor asks him why he did that , but Bernie doesn ' t tell him , only that the Doctor won ' t be going anywhere for a while . The Doctor demands to be released , but Bernie pulls a revolver out of his pocket and gets the Doctor to head further into the warehouse . Colonel Rook comes out from the shadows and reveals that the Doctor has fallen into his trap . The advertisement for Magpie Electricals had been placed in the newspaper by him . Rook has been monitoring Coal Hill for some time , ever since reports of unusual signs of technological activity appeared four months ago , at around the same time a series of thefts started occurring . The Doctor lies to Rook , denying any involvement in the thefts . Rook then reveals that he was then told of a girl with an unusual understanding of science , and who sometimes seemed to know exactly what people were thinking . The Doctor asks Rook what he ' s done to Susan . Rook tells him that Susan is safe . Rook comments on how well the Doctor has covered his tracks . Everything became clear to him when he noticed that there was no official documentation of any kind on either Susan or the Doctor . Rook tells the Doctor to admit that he and Susan are aliens from another world . The Doctor denies this and asks Rook who he is and what he wants . Rook tells him that he will help Britain with the war . Meanwhile , Susan is still with Cedric . Cedric admits that Susan was right about the Bob Dylan songs , they have got him thinking . Susan wonders where her grandfather is , as he said that he was going to pick her up . Susan is struck by another headache and she knows that something is wrong . Suddenly , people are attacking Susan again . Susan doesn ' t know anywhere that she and Cedric can run to , but he does . The two run off . The Doctor is still in the warehouse . He refuses to help Rook . Rook tries to convince the Doctor to help them , to use his alien knowledge to crush Britain ' s enemies . The Doctor denies being an alien again , pointing out that if he was an alien , he would also have a spaceship . Rook frowns , knowing that Bernie ' s attempt to search the junkyard turned up nothing except junk and an old police box . Rook insists that the Doctor will help him , and so will Susan . Rook ' s agents have told him that Susan ' s has great talents . He reveals that the enemy is conducting experiments with ESP . Susan will help Britain with their own experiments . She will have no choice but to help them , as Rook will be holding the Doctor prisoner . Cedric and Susan are running down the streets of the East End , trying to escape the people trying to attack them . Susan is having difficulty focusing , as her headache is overwhelming her . They hear the sounds of windows breaking , and realise that some of the people are attacking Rosa ' s . Cedric pulls Susan towards the bomb site , so they can pass through it to get to wherever Cedric is trying to go . Bernie is standing by the locked warehouse gate , worried at the growing disturbance in the streets . Rook asks the Doctor if he is responsible for what is happening . The Doctor denies this , and then realises that Susan is still out there . The Doctor begs Rook to let him out so he can find Susan . Someone bangs on the gate . It ' s Cedric , who has made it there with Susan . Rook tells Bernie to let the two in . Bernie quickly locks the gate up behind them , keeping their pursuers outside . The Doctor asks Susan if she is okay . Susan tells him about her headache . The Doctor helps Susan get to a chair , so she can sit down for a while . Susan notices Colonel Rook , and asks him why he is here . Cedric admits that Rook is his uncle . Susan is confused , so Rook tells Cedric to tell the full truth . Cedric is Rook ' s nephew , and also a spy that Rook had investigate Susan . Susan feels betrayed . The full mob of people has reached the warehouse , and is trying to break in . The Doctor asks Rook if there is another way out , to which Rook can only shake his head . The Doctor starts pacing , trying to figure out what really is going on . The Doctor remembers that the mob had referred to Susan and himself as aliens . He asks Susan if the mob is attacking only them . Cedric remembers that the mob is also attacking Rosa as well as another man named Winston . Rosa is from Germany , while Winston is from Jamaica . The Doctor realises that what the mob is talking about aliens , they are referring to foreigners . Something is affecting the part of the brain that controls the tribal instinct and is taking it to extreme levels in a way that only affects younger people . Whatever is affecting them is being caused by a hypersonic signal , which only affects children . This also explains Susan ' s headaches , as the signal is affecting her too , but her mind is strong enough to resist . Rook suggests that they fight their way out through the mob . The Doctor ignores him , working out how the signal is being transmitted . It is being transmitted via radio waves . Cedric understands , remembering the cryptic message from the future Doctor . It ' s all in the beat . Susan realises what Cedric is getting at . The signal is synchronising itself with particular music from the radio , causing anyone who listens to that music to be affected , the same music that the younger people of Coal Hill listen to . The Doctor wonders where the signal is coming from . He asks Cedric when the problem first appeared . It was four months ago , when the Doctor and Susan first arrived . Rook takes this to mean that the Doctor is behind this . The Doctor continues to ignore Rook and asks Cedric about other events that occurred in that time . The rest of the Mayfield Terrace was pulled down , as most of it had been destroyed in the war . Susan then remembers what Rosa had told them . Two bombs had been reported being dropped that night , but Rosa had seen three . Rosa had seen something that wasn ' t a bomb , something that was disturbed when Mayfield Terrace was pulled down . The source of the signal is at the bomb site , where Cedric was affected by it . The Doctor asks Rook if this is possible . Rook admits that the Nazis were experimenting with different kinds of weapons towards the end of the war , using materials that the Allied Forces has no knowledge of . A weapon to make people hate anyone who ' s different would cause chaos , paving the way for an invasion . The Doctor knows he needs to find a way to disrupt the signal , before the mob successfully breaks into the warehouse . He starts looking at all the technology on the shelves of the warehouse . Rook demands to know what the Doctor is doing . The Doctor tells him he is looking for the parts he needs to build a device to jam the signal . The Doctor grabs the items he needs and goes over to a workbench to assemble his device . The Doctor succeeds in constructing a device . He has Susan turn on her radio , and a Beatles song comes on . This kind of song is one that is carrying the signal , so the Doctor will need something that will counter it . Susan changes the station to one that plays a different kind of music , and the Doctor proclaims that this will do perfectly . He connects Susan ' s radio to his device . Rook asks him if the device will work . The Doctor tells him that they still need something that can reflect and transmit the Doctor ' s sonic beam to the bomb site , in order to cancel the signal . Rook realises a satellite will work , and pulls out a map of the world that also indicates the locations and trajectories of all of the satellites in orbit around Earth . Rook quickly finds Telstar , a satellite that will be perfect for the job , one that will be in range in ten minutes . The Doctor tells Susan , Cedric , and Bernie to try to hold off the mob for as long as possible , while he and Rook head up to the roof to set up the Doctor ' s device . Outside , the mob is using a heavy piece of timber from the bomb site to break down the gate . Bernie pulls out his gun , but Susan knocks it away . Cedric asks her if she is mad , but Susan points out that they can ' t just kill these people . Cedric thinks they should go to the roof , where they ' ll be able to fight them off better , but Susan reminds him that her grandfather needs all the time he can get to set up the machine . Susan tells Cedric he can go up to the roof , as the mob wants her . Susan remembers that her mind is strong enough to resist the signal . She might be able to use telepathy to break the signal ' s hold on the mob . The mob breaks down the gate and bursts into the warehouse . They advance on Susan , Cedric , and Bernie . Susan tries to use telepathy and momentarily succeeds . The mob stops for a moment , not sure why they were there , before the signal regains control and they advance again , however they were slower now . The people in the mob are partially fighting against the signal , but the signal has enough control to get them to continue to advance on the trio . On the roof , the Doctor and Rook are hurrying as fast as they can to set up the device . Rook gives the Doctor the coordinates of Coal Hill . The Doctor finishes the device and turns it on . The sonic beam is sent towards the satellite . The Doctor tells Rook that they will know if it worked within the next few minutes . Back in the warehouse , Susan is on the verge of collapsing from her efforts to hold back the mob with her mind . Her efforts have only delayed the mob , and Susan is now no longer able to hold them back . Cedric grabs a hammer and is ready to fight the mob , when the members of the mob collapse to the floor , unconscious . The Doctor ' s device has successfully blocked the signal . Cedric offers to help Susan to her feet , but Susan refuses , still hurt from Cedric ' s betrayal . Susan manages to get to her feet , as the Doctor and Colonel Rook return . The Doctor hugs his granddaughter , proud of her bravery . Rook asks the Doctor if it is all over now , to which the Doctor tells him that the enemy device will only be disabled for a short time , so they need to have it destroyed before it can activate again . Rook tells the Doctor that there is still a war to fight , and that the Doctor and Susan will still help them , but Cedric blocks him . After all , Susan and the Doctor have just saved their lives . Rook reminds Cedric about the war , but Cedric believes that the war he is thinking of is the wrong war . They were ready to use the Doctor and Susan as tools , making them no better than their enemy . Rook considers this , and agrees with Cedric . Rook promises the Doctor that his secret is safe , to which the Doctor only asks him , " And what secret would that be ? " Cedric apologises to Susan , who doesn ' t accept it . As far as she is concerned , her friendship with Cedric is over . The Doctor and Susan leave the warehouse . The Doctor tells her how proud he is of her , and of how she has proven how strong her mental abilities are . The Doctor suggests that the two of them work on that talent . However , he notices an odd look on Susan ' s face , and asks her what is wrong . Susan shudders and tells him that she has a feeling , possibly a premonition , that something terrible is coming , something that will affect everything that ever was , that is , and that will be . It won ' t come anytime soon , but in the future , and it will be the Doctor ' s destiny to face it , a destiny he can ' t escape .