The Dalek Invasion of Earth (TV story)


 * This article concerns the television story. For the similar film, see Daleks - Invasion Earth 2150 AD.

"Goodbye Susan. Goodbye, my dear..."

- The Doctor

The Dalek Invasion of Earth was the second story of Season 2 of Doctor Who. It saw the return of the Daleks who had proved so popular when they first appeared in Season 1. Terry Nation once again wrote this script, this time bringing the Daleks to Earth. This story also saw Susan part company with the Doctor, the first of his companions to leave.

Synopsis
The TARDIS materialises in London sometime after the year 2164. Dalek invaders are now ruling the Earth with the aid of humans converted into zombie-like Robomen, but they are opposed by a group of resistance fighters led by the wheelchair-bound Dortmun.

The travellers discover that the Daleks have established a huge mine in Bedfordshire, their aim being to remove the Earth's core using a huge bomb and replace it with a powerful drive system so that they can pilot the planet around the galaxy. Ian manages to create a barrier in the shaft in order to intercept the bomb. The resulting explosion destroys the Daleks and their mine and creates a huge volcanic eruption.

Susan has fallen in love with resistance fighter David Campbell, and the Doctor decides to leave her on Earth to find a new life with him, while he continues on his travels with Ian and Barbara.

World's End (1)
A man staggers towards the River Thames, wearing ragged clothes and a strange metal helmet. He screams, tearing the straps off the helmet, walks into the river and drowns himself. Near the same spot, the TARDIS materialises, the Doctor surmising from the surroundings that they have landed in London. Ian and Barbara are delighted they have returned home at last, but it is a curiously silent and deserted London. The Doctor is concerned about the decay they see around them and wonders about what year it is, fearing that it is nowhere near Ian and Barbara's time. Susan tries to look over a wall, but slips and twists her ankle, at the same time that the bridge under which the TARDIS has materialised collapses, burying the TARDIS and blocking the travellers' access to it. The Doctor and Ian decide to look around in a nearby warehouse for tools to help unblock the TARDIS door. Barbara remains behind to look after Susan. Barbara then goes to a river for water. But at the river she spies a strange eyeball that doesn't see her.

Exploring the abandoned warehouse, Ian and the Doctor are unaware they are being watched. From a window, Ian spies Battersea Power Station with its chimneys damaged, while the Doctor finds a calendar marked 2164. Barbara, who went to the river to soak a handkerchief for Susan's ankle, returns to find her gone and a dirty-faced man there instead. The man tells her that they have to get out of there before they get killed, and that Susan has been taken by someone called Tyler. He urges her to follow as the sound of automatic fire is heard in the distance. Meanwhile, in the warehouse, the Doctor and Ian stumble across a corpse, wearing the same strange helmet seen earlier. They also find an electronic receiver attached to the helmet and a whip on the body, and discover that the man has been stabbed to death. They decide to return to the others and spy a flying saucer hovering over the city.

Barbara is still following the man across the ruins of London. Tyler carries Susan down a flight of steps into an empty Underground station as Barbara catches up. Susan and Barbara demand that they find the others, but Tyler says that there is no time. Tyler activates a secret panel and David Campbell emerges from it, telling Tyler that he had a struggle with a Roboman and that they will have to tell Dortmun to change the storehouse. He also reveals that he saw the Doctor and Ian in the warehouse but thought they were enemies. Dortmun, a man in a wheelchair, arrives, and Tyler tells him that a saucer has landed at the heliport, and Dortmun says that this time they will be ready for "them". Dortmun is glad to see Susan and Barbara, as extra sets of hands, especially since Barbara can cook. David goes to find the Doctor and Ian. Dortmun asks him not to be long, as they need to go through the attack plans. Tyler takes Susan and Barbara below while Dortmun stays on watch, armed only with a knife.

Ian and the Doctor have arrived back at the TARDIS to find the women gone. Ian finds a poster forbidding the dumping of bodies in the river and muses, "Bring out your dead..." Was there a plague in the city? David spots them from a window but he also sees several Robomen converging on their position. The Doctor and Ian find themselves surrounded, but the Robomen only tell them to stop in flat tones. The two try and run for it, but turn only to see, rising from the Thames, the distinctive form of a Dalek.

The Daleks (2)
The Dalek orders that the Doctor and Ian be brought to the landing area, and warn the Doctor that resistance is useless and that they have already conquered the Earth. In the resistance base, the humans listen to Dalek propaganda broadcasts demanding their surrender. A young woman called Jenny tends to Susan's ankle while Barbara prepares food. Tyler and Dortmun debate about whether they are capable of attacking the Dalek saucer with the numbers they have. Dortmun shows off a new acid bomb that he has created, which he is confident will shatter the Dalek casings. David returns, reporting the capture of the Doctor and Ian. They have been taken to the heliport at Chelsea.

Ian is confused, as they saw the Daleks destroyed on Skaro. The Doctor explains that Skaro was a million years from the present — what they are witnessing is the middle period of Dalek history. Dalek guards usher the prisoners into the saucer. One human tries to escape and is exterminated. Back in the base, David explains that the Daleks operate on some of their human prisoners and turn them into Robomen, but the transfer operation is unstable and eventually the Robomen go insane and turn suicidal. The saucer is where the transfer takes place. On the saucer, the Doctor and Ian are put in a cell together with another prisoner, Craddock. Ian asks him how the invasion happened. Ten years before, meteorites brought a plague to Earth, splitting the Earth into small communities and unable to resist six months later when the Dalek saucers landed. Some humans were turned into Robomen, others destroyed or sent to the mining areas in Bedfordshire. Craddock does not know, however, what the Daleks want out of the ground.

The resistance plans the assault. Barbara suggests using the Robomen helmets as a disguise to get them close enough to use Dortmun's bombs. Meanwhile, the Doctor attempts to manipulate a device inside the cell, which he suspects to contain a key to the door. However, what he does not realize is that the device is an intelligence test. The Daleks have been observing him remotely, having earlier adjudged him more intelligent that the other humans from his earlier remarks. Solving the lock confirms their assessment, and the Doctor is taken away to be robotised. The Doctor is placed on a transfer table as outside the saucer, the resistance forces gather.

Day of Reckoning (3)
Tyler's attack group arrives, disguised as Robomen and prisoners. Susan, David and Barbara start throwing bombs from a nearby building. Tyler's group enters the saucer to try and free the prisoners while outside the Daleks scramble to mount a defence. Members of the group carry the unconscious Doctor away from the transfer table rush out of the saucer with the prisoners, using the bombs to cover their escape. The bombs, however, are ineffective. Dalek blasts and gunfire mix with the chaos of dying men as they scramble away. In the confusion, Barbara is injured and Ian remains behind on the saucer. Tyler is separated from the Doctor — he tells Dortmun back at the base that he is going to search for survivors of the raid and then leave London. Dortmun wants to go to the Civic Transport Museum, another gathering place, to get supplies so he can continue working on his bombs. Barbara and Jenny agree to go with him.

In the saucer, the Black Dalek relays an order from Supreme Command to destroy London with firebombs. The saucer lifts off, on its way to the mines. Ian emerges from his hiding place, only to bump into a robotised Craddock, who is escorting a prisoner for transfer. Ian struggles with Craddock, who stumbles against the transfer machinery and is electrocuted. The man introduces himself as Larry — he had stolen aboard the saucer in order to hitch a ride to Bedfordshire to find his brother. They get rid of Craddock's body via a disposal chute.

David and Susan hide from Dalek patrols, and listen in horror as the sounds of extermination echo around them. Susan wishes she could just go back to the TARDIS and get out of here, and suggests that she could persuade her grandfather to take David along. David tells her that running away does not solve all problems, and besides, Earth is his planet and he cannot abandon it. Susan thinks about how she has never had a place she could call home or her own identity. David says that someday she will. Suddenly, they hear a noise — Baker, carrying the drugged Doctor. Baker says he will be heading for the Cornish coast, but, just as he leaves the others, he is intercepted and exterminated by a Dalek patrol.

On the streets of London, deserted except for Daleks, Jenny, Barbara and Dortmun avoid the patrols and make it to the museum. There, Dortmun finds his notes and determines the fault was not with the bombs but with the dalekanium casings of the Daleks. He comes up with a new formula for the acid bomb, and wants Barbara to take his notes to the Doctor. Barbara tells him he can give it to the Doctor himself, but once she leaves the room, Dortmun leaves his notes behind and goes outside to try the new bombs against the Daleks himself. He calls out defiantly to the Daleks, throwing a bomb at them as they exterminate him. However, the new bomb fails to make an impact. Jenny and Barbara make their escape.

The Doctor begins to get feeling back in his legs. Susan tells him that David suggests heading north to meet with a resistance group there but the Doctor says that he they should try to reach the TARDIS, tetchily observing that Susan seems to trust David's word over his. Susan protests that it is simply because David knows this time better. David returns, saying that there are patrols everywhere, and asks the Doctor for his advice as he is the senior member of the party. Somewhat mollified by the gesture of respect, the Doctor "suggests" to David that they make their way North. Susan is pleased. Hidden in the saucer, Larry tells Ian of his brother Phil's theory that the Daleks want the magnetic core of Earth. The saucer finally lands and the Daleks disembark with their new workers and the Roboman guards. Ian and Larry leave through the disposal chute and make for the nearest tunnel. Back in London, two Robomen place a Dalek firebomb near the Doctor, Susan and David's hiding place, and it begins to tick down.

The End of Tomorrow (4)
The Doctor passes out, leaving David and Susan to defuse the firebomb on their own. David uses acid from one of Dortmun's bombs to burn through the casing, and removes the timing mechanism before it can trigger the explosive. David suggests they leave the Doctor behind for the moment while they search for a way through the sewers out of London. Susan does not like the idea of leaving the Doctor alone but David says they have no choice. Meanwhile, Barbara and Jenny fix up a lorry from the museum in preparation to drive up to Bedfordshire. There, Larry and Ian are moving through the countryside, spotting a group of human slaves pulling a carriage of metal parts towards a mine shaft and hearing the sounds of machinery. Trying to get under cover, they meet a man called Wells, who thinks they are escaped workers. He tries to cover for them, however, when a Roboman comes to take them for selection to be robotized. Ian and Larry help Wells when the Roboman attacks him, and knocks the Roboman out. Wells tells them he was here to meet Ashton, a black marketeer. Ian wants to meet Ashton, hoping he has a way to get him back to London. Wells tells Ian that the Daleks have destroyed the city.

In London, Barbara and Jenny ride out of the museum in the lorry, past Dortmun's corpse. They run a roadblock, Barbara crashing the lorry through the Daleks, but their position is reported back to the saucer, which gives orders to intercept them. Jenny and Barbara manage to leap out of the lorry before it is destroyed by the saucer. David and Susan move through the sewers, where they meet Tyler, who warns them of alligators in the sewers. Susan hopes that she will never become as cynical as Tyler, but David says that one day it will be all over and they can rebuild the planet from the start. Susan finds the idea of a fresh start exciting. While exploring, Susan nearly falls into the jaws of an alligator, but Tyler and David manage to rescue her. They climb out of the sewers, Tyler having found the Doctor who has now recovered. In Bedfordshire, Larry and Ian avoid the monstrous Slyther, the pet of the Black Dalek, and while hiding, meet Ashton. Ian asks if Ashton can take him to London, but Ashton refuses unless Ian can pay in gold or other precious metals. Wells arrives, trading jewellery for food, but the Slyther attacks as they are eating. Ashton is killed, while the Slyther approaches Larry and Ian, who are trapped on the edge of a sheer drop.

The Waking Ally (5)
The two jump into a mining bucket suspended over the pit, and although the Slyther tries to jump after them, Ian hits it with a rock and causes it to fall to its death. Before Ian and Larry can climb out of the bucket, it starts to descend. In London, Robomen pursue the Doctor and his party back into the sewers. Tyler and David lay an ambush, and manage to subdue them. Meanwhile, Jenny and Barbara find a hovel in the countryside with two women, seeking shelter from a storm. The women are left alone by the Daleks because they make clothes for the slave workers in exchange for food. Barbara offers them food in exchange for staying the night. The older woman sends the younger one to deliver clothes, but she has actually gone to bring the Daleks, who capture Jenny and Barbara.

Ian and Larry finally reach the bottom of the shaft, and jump down the last twelve feet before the bucket tips over. Larry injures his knee as he falls, however. As he hides, Ian looks around, puzzled that the mine only seems to be made for shifting rocks and not processing ore. Larry repeats his brother's theory that the Daleks are after the Earth's core. Trying to blend in with a working party, they are confronted by a Roboman — Larry's brother Phil. Larry pleads with Phil, trying to make him remember who he is, but Phil prepares to shoot them. Larry tells Ian to run as Phil shoots, mortally wounding Larry even as Larry strangles him. Both die, with Phil's last word being a strangled, "Larry..." Alarms sound as the workers seize their chance for freedom.

In the countryside, Susan and David share a tender moment around a campfire, kissing before the Doctor and Tyler return. The Doctor has deduced the reasons why the Daleks are here — something deep beneath the Earth, tampering with the forces of creation. Ian makes his way deeper into the mine, noticing Jenny and Barbara, who have joined a working party. Jenny is in despair, but Barbara says they must find the control room, as that would be what the Doctor would do. Ian keeps hidden, but tells Wells to pass word to Barbara that he is here. Barbara tells the Daleks that the rebels are planning an attack, and shows them Dortmun's notes. She asks to speak to someone in authority and they agree to take her to the Black Dalek. Meanwhile, the Daleks report to the Black Dalek that they have almost reached the outer crust of the core. All that remains is to set up and the penetration explosive. Once the core is removed, they will replace it with a power system that will allow the Daleks to pilot the planet anywhere in the universe. Unfortunately, Ian has chosen the penetration device as a hiding place, and it is moving into position to be dropped down the main shaft.

Flashpoint (6)
Ian disconnects some wires inside the casing, stopping its descent. The Robomen start pulling it back up the shaft, while Ian manages to open a panel at the bottom of the casing and climb out. A Dalek spots him, however, and severs the rope, causing Ian to slide down the shaft and fall against a door, which knocks him senseless. At that point, Barbara and Jenny are escorted into the Dalek control room. The Black Dalek orders that all humans be moved to the lower galleries to be exterminated in the final blast. The Daleks relay the orders to the Robomen through a microphone, which Barbara notices. The Black Dalek interrogates Barbara and she tries to stall by telling them of an elaborate mutiny that involves Red Indians, the Boston Tea Party, Robert E. Lee and Hannibal, panicking the Daleks momentarily but not enough — she is recaptured when she tries to use the microphone. She and Jenny are immobilized in clamps to await destruction when the bomb explodes.

Outside, the Doctor tells Susan and David to destroy an aerial on the far side of the mine with Dortmun's bombs. He and Tyler will go into the mine itself. Ian regains consciousness outside the lower gallery where the Robomen are hauling timber. When they leave, he puts some of these spars into the bomb shaft, where it stops the progress of the bomb before it can reach the crust. The Daleks are unaware of this, however, and evacuate. The Doctor neutralises the warning system and he and Tyler make their way into the control room, where they free Jenny and Barbara. He explains that David and Susan's mission will immobilize the Daleks. As the Daleks detect the Doctor's presence in the control room, a patrol approaches, but David and Susan succeed and the Daleks stop in their tracks. Barbara and the Doctor use the microphone to tell the Robomen to turn against the Daleks. Human workers and Robomen break into open revolt and stream out of the mine.

Ian is reunited with the others. From where the bomb has stopped, it will not succeed in penetrating the crust but will still produce a gigantic explosion. As they reach higher ground, the bomb explodes, making the ground around the mine collapse and cause an entirely new phenomenon — a volcanic eruption in England. The Dalek saucer is caught in the upward thrust of the explosion. The invasion is over.

Back in London, the resistance helps the Doctor uncover the TARDIS as the chimes of Big Ben herald a new beginning for mankind. Susan is saddened at the prospect of leaving, and the Doctor seems to sense this. He goes into the TARDIS while Susan goes to say good-bye to David, who tells Ian he wants to work the land, see things grow again. Barbara takes Ian back into the TARDIS so they can leave Susan and David alone. David tells Susan that he loves her and asks to stay and marry him, offering her the place and identity she has been yearning for. Susan admits she loves him too, but she also needs to look after her grandfather, and begs him not to make her choose between them. The Doctor, having heard all this, makes Susan's choice for her. He double-locks the doors of the TARDIS, preventing Susan from entering. He tells Susan through the scanner that she will always be his grandchild, but she is a woman now, and he wants her to have a home; David will take care of her. Saying one last good-bye and saying he will one day return, he makes the TARDIS dematerialise.

Susan looks forlornly around the empty space where the TARDIS used to be, fingering the TARDIS key on the chain around her neck. David reaches his hand out to her and she takes it, dropping the key onto the ground and walking away.

Cast

 * The Doctor - William Hartnell
 * Ian Chesterton - William Russell
 * Barbara Wright - Jacqueline Hill
 * Susan Foreman - Carole Ann Ford
 * Carl Tyler - Bernard Kay
 * David Campbell - Peter Fraser
 * Dortmun - Alan Judd
 * Robomen - Martyn Huntley, Peter Badger
 * Dalek Operators - Robert Jewell, Gerald Taylor, Nick Evans, Kevin Manser, Peter Murphy
 * Dalek Voices - Peter Hawkins, David Graham
 * Insurgent - Robert Aldous
 * Jenny - Ann Davies
 * Jack Craddock - Michael Goldie
 * Thomson - Michael Davis
 * Baker - Richard McNeff
 * Larry Madison - Graham Rigby
 * Wells - Nicholas Smith
 * Slyther Operator - Nick Evans
 * Ashton - Patrick O'Connell
 * The Women in the Wood - Jean Conroy, Meriel Hobson
 * Roboman - Peter Diamond (uncredited), Adrian Drotskie (uncredited), Bill Moss (uncredited), Reg Tyler (uncredited)
 * Double for William Hartnell - Edmund Warwick (uncredited)
 * Revolting Prisoners - Robert Aldous (uncredited), James Appleby (uncredited), Nigel Bernard, (uncredited), Jo Calvert (uncredited), Leslie Conrad (uncredited), George Dare (uncredited), Stenson Falke (uncredited), Daphne Green (uncredited), Margo Hanson (uncredited), Jonas Kurchi (uncredited), Tony Lambden (uncredited), Maureen Lane (uncredited), Peter Morton (uncredited), Bill Moss (uncredited), Rex Rashley (uncredited), John Sackville West (uncredited), Donald Simons (uncredited), Rosina Stewart (uncredited), Fred Taylor (uncredited), John Timberlake (uncredited), Graham Tonbridge (uncredited), Alan Wakeling (uncredited), Tony Walsh (uncredited), Les Wilkinson (uncredited), Jan Willis (uncredited)
 * Extras - John Censor (uncredited), Susanne Charise (uncredited), Roy Curtis (uncredited), John Doye (uncredited), Otto Friese (uncredited), Pat Gorman (uncredited), David Graham (uncredited), Joe Hardesty (uncredited), Peter Holmes (uncredited), Peter Honeywell (uncredited), Bill McAllister (uncredited), Roma Milne (uncredited), Patricia Phipps (uncredited), Steve Pokol (uncredited), Tony Poole (uncredited), Molly Prescott (uncredited), Michael Reed (uncredited), Leonard Woodlow (uncredited)

Crew

 * Writer - Terry Nation
 * Director - Richard Martin
 * Producer - Verity Lambert
 * Script Editor - David Whitaker
 * Designer - Spencer Chapman
 * Assistant Floor Manager - Christina Lawton
 * Associate Producer - Mervyn Pinfield
 * Costumes - Daphne Dare
 * Costumes - Tony Pearce
 * Fight Arranger - Peter Diamond
 * Film Cameraman - Peter Hamilton
 * Film Editor - John Griffiths
 * Incidental Music - Francis Chagrin
 * Make-Up - Elizabeth Blattner
 * Make-Up - Sonia Markham
 * Production Assistant - Jane Shirley
 * Special Sound - Brian Hodgson
 * Studio Lighting - Howard King
 * Studio Sound - Jack Brummitt
 * Theme Arrangement - Delia Derbyshire
 * Title Music - Ron Grainer

Ratings

 * World's End - 11.4 million viewers
 * The Daleks - 12.4 million viewers
 * Day of Reckoning - 11.9 million viewers
 * The End of Tomorrow - 11.9 million viewers
 * The Waking Ally - 11.4 million viewers
 * Flashpoint - 12.4 million viewers

Myths

 * The story is set in 2164 (Although the Doctor and Ian find a calendar dated 2164 there is no indication how long the calendar has been in the warehouse).
 * The Daleks are defeated as they are susceptible to the Earth's magnetic forces (They are defeated by the explosion at the mine. The idea of the Daleks being susceptible to Magnetic forces is a concept from the Movie Daleks - Invasion Earth 2150 AD).

Filming Locations

 * Trafalgar Square, London
 * The Third Way in Wembley, London
 * Royal Albert Hall, London
 * The Palace of Industry, London
 * Whitehall, London
 * The Embankment, London
 * Westminster Bridge, London
 * St Katherine's Dock, London
 * White City Underground Station, London
 * Hammersmith Bridge, London
 * Ealing Studios
 * St John's Hole Quarry, Kent
 * Riverside Studio 1, Hammersmith, London

Discontinuity, Plot Holes, Errors

 * If this is during the middle of Dalek history, why did the Daleks on Skaro not use disks on their backs to exit their city? It's not the middle of Dalek history. The Doctor was clearly mistaken when he said this. The disks appear to only be needed by this group of Daleks for this particular mission of theirs. And indeed, in episode 2 the Doctor explains exactly this to Chesterton. 
 * The Slyther changes appearance between episodes 4 and 5 as the production team were not happy with its appearance. Many species change their appearance easily.
 * When Ian and Larry meet Ashton the Slyther cries for the first time, over Chesterton's line. He does not pause nor otherwise express surprise or horror, despite never having heard the Slyther before.
 * Two studio technicians are visible outside the Dalek saucer in episode 2.
 * Jenny and Barbara have to hold their own neck restraints in place. It is not a problem it looks more like they are trying to pull them off or give themselves room to breath.
 * When the Daleks are in Trafalgar Square, cars can be seen to drive past. Pushing it somewhat, but these could (just) be Robomen on vehicle-based patrol, or the resistance cells making use of discarded vehicles, as Barbara and Jenny later do.
 * Pleasure cruisers can still be seen on the Thames.
 * Boom mike shadows are visible in episodes 3 and 6. Could be trees or lampposts.
 * Why do the Daleks need intelligence tests to determine who can become Robomen when they are mindless zombies? Allegedly, the more intelligent the human, the longer the Roboman will function. Also, they may be required to perform mental calculations. Or possibly this test is to remove the clever ones?
 * Just what is the Dalek doing in the river in episode 1? (The Daleks are in dalekanium shells, and therefore cannot distinguish between air and water. The Daleks are probing the Thames for some reason; possibly a scientific expedition- are the fish a threat to the invasion?! or it is searching for the suicidal roboman's body.
 * The Black Dalek, before addressing the humans, clears its throat. Presumably, all superior Daleks have certain emotions and a limited control over themselves (DW: The Stolen Earth) Who says the Kaled mutants don't have throats of some sort at this point in their development?
 * Why did the Daleks locate their mine in Bedfordshire rather than somewhere where the Earth's crust is thin? How do the Daleks know where the Earth's crust is thin? They probably choose a small area that would have little resistance; if they drilled in New York there may have been more resistance.
 * During the first episode, while the Doctor and his companions are exploring their materialization place next to the Thames, the TARDIS windows are clearly propped open (inwards). Examples are at 2 minutes 12 seconds through 2 minutes 16 seconds, and elsewhere during the same scene. Were they just traveling through space and time with the windows open? The TARDIS exterior faithfully matches a genuine police box - the windows are seen to be open in other early stories such as The Web Planet. The TARDIS shell is clearly not as simple as a wooden exterior, which would imply that it cannot be airtight. The Doctor later describes to Donna that there is a shield protecting the interior. It has been stated that the interior is in another dimension to the exterior (such as The Robots of Death).
 * After taking Barbara and Jenny prisoner, the Dalek that takes them across the control room of the Dalek saucer can be seen bumping into the Black Dalek.
 * In episode 4 when they meet Ashton, the interior is seen to have a window - something not seen on the exterior. Not on the side we see.
 * In the prison where the Doctor is held on the ship, another set behind the railings can clearly be seen, complete with Daleks moving about. It's part of the same ship, which of course contains Daleks.
 * At one stage in episode 2, a Dalek can be heard saying "All" - the start of the next line (This is because it was pre-recorded, and couldn't stop the recording in time). The Dalek was saying something and was interrupted.
 * The paint design of the Black Dalek changes after episode 2. The first one was the commander of just the flying saucer, the second one was in command of EVERY Dalek on Earth
 * The use of cardboard Daleks outside their ship. Are these to fool attackers without wasting Daleks?
 * During episode 5, when the Black Dalek moves through the door, a production assistant is clearly visible to the Dalek's right.
 * The 'It is forbidden to dump bodies in the river' sign is visible during the miners' revolt in episode 6. This is because the two sets were next to each other and weren't blocked off. There's no reason to assume they don't have the sign posted in multiple places.
 * Wouldn't people by this time already have knowledge of the Daleks considering Doomsday/Army of Ghosts, Daleks in Manhattan/Evolution of the Daleks, Dalek and all other episodes set in the 20th or 21st centuries? There's no evidence that they had not heard of Daleks before the Invasion. And also the events of Daleks in Manhattan and Evolution of the Daleks only affected around 100 people, all which would be dead by now. There is also evidence in Torchwood that the UN is covering things up. As well, it is possible for history to change. The Battle of Canary Wharf and the stealing of Earth may not have happened in this version of history.
 * If the Daleks are drilling to the Earth's crust, wouldn't that blow it up? They have other methods then the ones used in Inferno. The Doctor mentions that they are manipulating living energy to avoid explosions.
 * Judging by what Susan says to Tom about 'Grandfather getting old now' and her needing to look after him, it seems that she doesn't know about regeneration. Perhaps it would be hard for her to explain regeneration to Tom or perhaps she knows when he is going to regenerate and she wants to be with him. Also, she does not know for sure that he will regenerate into a younger body. (All she says is that he's getting old now, which does make things physically difficult for him at times. This makes no implications whatsoever other than that Susan cares about the Doctor's well being.)
 * When Tyler and the Doctor are hiding behind the walls. The last Dalek to pass by has the eyestalk pointed in the Doctor's direction, yet he does not notice Tyler or the Doctor.
 * When Barbara and Jenny are taken to the Dalek command centre, they devise a plan against the Daleks. They talk in full voice, while the Dalek guard is directly behind them. Its only response is a command to 'stop talking'. As the dalek that comes out of the river in episode 2 says they have heard in the time that they have controled the earth many similier plots to over throw them that have all failed so they have properly got to a point where they don't pay any atention to them any more since they know that they are going to fail. 
 * In Episode 5, the Dalek supervising the mine clearance has broken speech-synch lights, and instead (for some bizarre and impractical reason) chooses to wiggle its eyestalk about while talking (which must make it rather difficult to give orders and keep an eye on its slave workers at the same time).

Continuity

 * The Cybermen also developed the technology to steer whole planets, and did so with their homeworld Mondas in DW: The Tenth Planet.
 * The Doctor and Susan are briefly reunited in DW: The Five Doctors.
 * The Seventh Doctor returned to the scene where Susan dropped her TARDIS key and recovers it in NA: GodEngine. This novel also serves as a prequel to this story.
 * The Doctor is confronted by a Dalek agent attempting to make the invasion happen earlier, in NA: Return of the Living Dad.
 * The Third Doctor encountered an alternate reality in which the Daleks had successfully invaded Earth in DW: Day of the Daleks.
 * The Doctor returns several years later in EDA: Legacy of the Daleks, Susan also reappears in the novel.
 * In BFA: The Mutant Phase the Doctor and Nyssa encounter an alternate world which shares some events with this story.
 * MA: Venusian Lullaby follows directly on from this story
 * This is arguably the earliest story that would have been affected by the events of the alternate reality seen in DW: Turn Left. In that story, London is destroyed by a replica of the Titanic in 2008, making it highly unlikely that the city would be rebuilt in time for the events of this serial. Donna travelled back in time to stop her earlier self in the 'present' (2009), and thus that world never made it beyond it's own version of 2009.
 * The Tenth Doctor recalls the events of this adventure while at the Shadow Proclamation with Donna investigating the disappearance of the Earth. (DW: The Stolen Earth)

Timeline

 * This story occurs after PDA: The Time Travellers
 * This story occurs before MA: Venusian Lullaby

Novelisation

 * Main article: Doctor Who and the Dalek Invasion of Earth


 * Novelised as Doctor Who and the Dalek Invasion of Earth in March 1977 by Terrance Dicks.

Motion picture adaptation
The story was adapted for the movie 1966 Daleks - Invasion Earth 2150 AD starring Peter Cushing. It was the second and, to date, final film to be based upon episodes of the televised series. Numerous changes were made to characters and story for the film, and a key plot element - Susan leaving the Doctor - is eliminated entirely.

DVD, Video, and Other Releases
DVD Releases

Released as Doctor Who: The Dalek Invasion of Earth in a two-disc set.

Released:
 * Region 2 9th June 2003


 * PAL - BBC DVD BBC1156


 * Region 4 13th August 2003
 * Region 1 7th October 2003


 * NTSC - Warner Video E1813

Contents:
 * Future Memories Documentary - A look back at the story by cast and crew.
 * Future Visions Documentary - A look at the designs of Spencer Chapman.
 * Talking Daleks Documentary - A look at the creation of the Dalek voices.
 * Now and Then - The locations revisited.
 * Script to Screen - How the story was shot in studio.
 * Whatever Happened to ...?: Susan - A BBC radio play starring Jane Asher as Susan (audio only - UK tx: 9th July 1994)
 * Rehearsal Film - Behind the scenes footage from 1964.
 * Dalek Cakes - A clip from Blue Peter.
 * Trailers
 * CGI Effects
 * Photo Gallery
 * Production Subtitles
 * Easter Eggs (2 featuring Sid the Slyther)
 * Commentary: William Russell, Carol Ann Ford, Richard Martin, and Verity Lambert

Rear Credits:
 * Starring William Hartnell
 * By Terry Nation
 * Produced by Verity Lambert
 * Directed by Richard Martin
 * Incidental Music by Francis Cahgrin
 * Cover by Clayton Hickman


 * Whatever Happened to ...?: Susan
 * Starring Jane Usher
 * Written by Adrian Mourby
 * Produced by Brian King

Notes:
 * Editing for DVD release completed by Doctor Who Restoration Team.

Video Release

Released as Doctor Who: The Dalek Invasion of Earth in a two-tape set consisting of two separate cassette cases held together by a plastic band.

Released:
 * UK May 1990


 * PAL - BBC Video BBCV4353


 * US February 1994


 * NTSC - CBS/FOX Video 5947
 * NTSC - Warner Video E1202

Notes: The 'Next Episode' caption has been removed from Episode 6.

References in other programmes
The Doctor's final speech to Susan ("Just go forward in all your beliefs...") is quoted verbatim in The Doomsday Armageddon Apocalypse, the 13th and final episode of the US science fiction series, The Middleman in 2008. Due to the show's cancellation by ABC Family, however, the episode was never actually filmed. Instead, the show's cast performed the episode live during the 2009 San Diego ComicCon in July 2009; a comic book adaptation of the episode was released by Viper Comics in August 2009.