[[quoteright:300:http://static.tvtropes.org/pmwiki/pub/images/robotswheee.png]]
[[caption-width-right:300: Huh... where's [[http://www.youtube.com/watch?v=RcH-3d-BZn4 Ben Stein]] when you need him?]]
->'''Leela:''' Doctor, what is "robophobia"?\\
'''Doctor:''' It's an unreasoning dread of robots. You see, most living creatures use non-verbal signals. Body movement, eye contact, facial expressions, that sort of thing.\\
'''Leela:''' Body language!\\
'''Doctor:''' Exactly. But while these robots are humanoid, presumably for aesthetic reasons, they give no signals. [[UncannyValley It's rather like being surrounded by walking, talking dead men]].

This serial begins in the recreation room of a giant sandminer ship belonging to a civilisation utterly dependent on robots. The workers discuss the urban legend of a guy whose arm was ripped off by a robot massaging him. But of course, they all know the robots have tons of safety systems in place and that they could ''never'' kill a human, [[TemptingFate right?]] Just then, the robots announce that they've detected a sandstorm, which stirs up ores in the sand that are worth a fortune. One poor RedShirt, Chub, goes into the storage room to collect instruments for a weather balloon when he's strangled by... go ahead, guess. Thus begins a round of Creator/AgathaChristie-style paranoid accusations.

Enter the Fourth Doctor and Leela, who materialize in one of the sandminer's scoops. They're brought out by two robots and locked in a room, as the workers of course suspect that the two killed Chub. It doesn't help that after they escape, the two are separately caught in the same rooms as dead bodies #2 and #3. So, the blame game enters Round Two; the crew cannot decide whether the Doctor and Leela did it or one of their own. At any rate, they're locked up in iron shackles in the robot storage room. When a rather nervous man named Poul frees the two out of belief in their innocence, the Doctor points out that they all completely overlooked a possible suspect: the robots. Poul laughs; the robots couldn't possibly kill a human!

While the Doctor tries to convince Poul otherwise, a woman named Zilda goes into Commander (and LargeHam) Uvanov's room and announces over a loudspeaker that she knows he's the murderer, but before she can explain how or why she gets strangled. For those watching at home, the body count is now up to 4. Suddenly, the ship shakes! Turns out, the ship has been sabotaged, and RedShirt repairman Borg [[Franchise/StarTrek (No, not that Borg)]] has become dead body #5. The ship can't handle the stress and is about to blow up, but the Doctor cuts out the power and gets a man named Dask to repair the motors so the ship won't sink into the sand. Leela bandages up the hand of acting commander Toos, who heads to her quarters.

Suddenly, a robot named D84 reveals that it and Poul are undercover agents for the mining company. They were placed on board the miner due to threats of a robot revolution by MadScientist Taren Capel, who was raised by robots and therefore a bit funny in the head. The Doctor and detective D84 search the miner for proof that Taren Capel is on board, and find a secret workshop where the robots' programming has been changed to enable them to kill humans. He tells Toos over the communications system to get the others and head for the command deck. But as soon as she can get to the door, she's blocked by a strangle-happy robot and just barely gets away by making the door slam onto its hand. Leela manages to find Poul, but he's too busy lying on the ground in the fetal position while he screams about how the robots have always controlled him. Meanwhile, it dawns on the Doctor and D84 that "Dask" is really Taren Capel, and he wants to liberate robots by giving them the ambition to take over civilization. (Meanwhile, Leela makes her way to Toos' bedchambers and the two engage in some very rather sweet LesYay for a bit.) Taren Capel (now wearing the robots' clothes and wearing facepaint to mimic them) gives his order to the robots: destroy all remaining humans on board. The Doctor realizes that this is the end of this civilization, as the robots they so depend on will become a source of overwhelming fear.

The Doctor comes up with a plan to destroy the robots. They're all being controlled by one particular robot: [=SV7=]. If it dies, the others will stop killing. He uses parts from a broken robot to creates a final deactivator -- a device that will destroy any still functioning robots at close range. At the same time, Uvanov and Toos have arrived at the command deck and built makeshift anti-robot bombs, which they proceed to kick robo-ass with.

The Doctor hides Leela in Taren's workshop with a canister of helium gas, telling her to release it slowly when Taren comes in. The Doctor hopes that this will change Taren's voice, so his robots -- unable to recognize him -- won't obey his orders.

Taren arrives and damages D84, but the robot is able to activate the Doctor's device to destroy a killer robot, knowingly sacrificing itself in the process (Dead Body #6...[[WhatMeasureIsANonHuman ish?]]). Leela releases the helium gas, causing Taren's voice to become high-pitched and squeaky, and Taren is killed by [=SV7=] when it fails to identify his voice. The Doctor then destroys [=SV7=] with a laser probe.

The Doctor explains that he used his own [[ContinuityNod respiratory bypass system]] to keep his CompellingVoice intact, and ponders a bit about how this society might now crash in on itself. He and Leela vworp off.

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A radio spinoff based on this episode, ''[[http://en.wikipedia.org/wiki/Kaldor_City Kaldor City]]'', was produced by Magic Bullet Productions and stars many of the original actors.

David Collings, who appeared here as Poul, went on to play an alternate version of the Doctor in the AudioPlay/BigFinishDoctorWho episode [[Recap/BigFinishDoctorWhoUnboundE3FullFathomFive "Full Fathom Five"]].

!!Tropes
* AlternateCharacterInterpretation (InUniverse): It's stated by Poul that Uvanov left Zilda's brother out to die ten years before because he didn't want to waste time and money. Later, Uvanov reveals that he in fact tried to save him when he came down with robophobia and panicked. The boy's father didn't want the boy thought of as a coward and had the records altered.
* AndroidsAndDetectives: D84 and Poul.
* BaseOnWheels: The Sand Miner.
* BizarreAlienBiology: The reason the Doctor's voice didn't go all squeaky.
* DeadpanSnarker: [=SV7=] gets in a surprising (for a robot) amount of snark, notably when the Doctor escapes by throwing his hat and scarf onto V5, and V4 promptly starts strangling his fellow robot.
--> '''V4:''' Kill. Kill. Kill.
--> '''V5:''' Do not kill me.
--> '''[=SV7=]:''' V4, that is not the Doctor.
--> '''V5:''' Do not kill me.
* DepthDeception: The Doctor's explanation for the whole "bigger on the inside" thing. One box is actually larger than another, but appears smaller because it's far away. The TARDIS uses transdimensional engineering to put two similar spaces in the same place, while keeping those relative sizes.
* EasilyDetachableRobotParts
* EliteMooks: [=SV7=].
* EveryoneIsASuspect
* EvilGloating
* FreakOut: Poul suffers a really horrible one when he finds a deactivated robot with fresh human on its fingers.
* HeliumSpeech
* HeroicSacrifice: D84.
* HoistByHisOwnPetard: Taren Capel.
* HollywoodScience: The Doctor's explanation to Poul that bumblebees fly even though that's "impossible" is an urban legend which has been traced back [[http://en.wikipedia.org/wiki/Bumblebee#Flight to at least 1934]] if not earlier and is based on applying equations to bumblebee flight that were known to be the wrong ones even back then.
* JerkAss: Uvanov. At first, he seems to care about little more than getting as much sand (read: money) as possible. Of course, this is before he realizes how truly screwed he is.
** JerkWithAHeartOfGold: When he tells the story of what Happened to Zilda's brother it's clear he's haunted by the memory, and tries to keep Poul calm.
* JustBetweenYouAndMe: Subverted:
-->'''The Doctor''': I see. Youre one of those boring maniacs whos going to gloat. Are you going to tell me your plan for running the universe?
-->'''Taren Capel''': Oh no Doctor. Im going to burn out your brain. Very very slowly.
* MachineMonotone: Much less severe than usual for the show. The result is somewhat sing-song-y, which just makes it that much creepier.
* MadScientist: Taren Capel.
* MobileFactory
* {{Mooks}}: The titular robots.
* MySpeciesDothProtestTooMuch: D84 is the only good robot in this serial -- though to be fair, the others didn't start out evil, and the one having its "good" programming rewritten on the operating table is ''very'' distressed throughout the process.
* NiceHat: The workers have some... odd headgear.
* PerspectiveMagic: The Doctor tells Leela that that this is the principle that enables the TARDIS to be much bigger on the inside than on the outside.
* RedEyesTakeWarning: An effect of the manner in which the robots are reprogrammed.
* RemovingTheHeadOrDestroyingTheBrain: An absurdly high number of robots take laser probes to the head.
* RobotBuddy: D84.
* ShoutOut: Robophobia is officially known as "Grimwade's Syndrome", a shout out to production assistant (later in the 1980's to be a Who director and writer) Peter Grimwade, who had complained that all the stories he worked on seemed to involve evil robots... Poul's full name is stated in a [[Literature/PastDoctorAdventures novel]] by Boucher; it's [[Creator/PoulAnderson Ander Poul]]. Likewise, Taren Capel recalls [[Theatre/{{RUR}} Karel Capek]], inventor of the word "robot", and Uvanov is reminiscent of [[Creator/IsaacAsimov Asimov]].
* TheSpeechless: The robots are divided between "Dums" that cannot speak and "Vocs" that can, a trope originated by Creator/IsaacAsimov. In addition, "Super Vocs" like [=SV7=] have advanced intelligence and command the lesser 'bots.
** {{Lampshaded}} by D84 near the end of part 3:
--->'''D84''': This is a communicator. It can function on either human or robot command circuits. Would you like to use it? ''I'' cannot speak...
* {{Spinoff}}: [[http://www.kaldorcity.com/ Magic Bullet Productions]] have produced plays centered around this civilization and their robots. Russell Hunter reprised his role of Uvanov for them.
* StandardFemaleGrabArea: Used on [[ActionGirl Leela]] and immediately subverted when she [[GroinAttack kicks Uvanov in the goolies]] and threatens to cripple him.
* StarshipLuxurious: The mining ship is quite luxurious, despite being crewed by people desperately hoping for a good strike.
* StrappedToAnOperatingTable
* TenLittleMurderVictims
* ThreeLawsCompliant: The robots are more or less presumed to be, before Taren Capel starts messing with them.
* UncannyValley (InUniverse): The robots themselves, with their blank expressions and creepy sing-song voices. The Doctor [[LampshadeHanging hangs a lampshade]] on this: see the page quote.
* UndercoverCopReveal
* WoundedGazelleGambit: Daz tries this in order to trick the remaining human survivors into letting him in their control room. Fortunately for them they listened to The Doctor and refused to let anyone in.
* TheXOfY
* YouLookFamiliar: David Collings and David Bailie went on to play parts in AudioPlay/BigFinishDoctorWho.
* YourHeadASplode: The effect of the "final deactivator" on nearby robots.
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