[[quoteright:350:https://static.tvtropes.org/pmwiki/pub/images/prisoner_checkmate_live_set.png]]
[[caption-width-right:350:Number Six seems to accept that he's a pawn in the game.]]
Number Six has an idea about how to discover which of his fellow Villagers are prisoners, and uses it to form an escape committee.
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!! Tropes
* AgentProvocateur: Unfortunately on the night of the escape Number 58 becomes paranoid that Number Six is an agent provocateur trying to incite them, so denounces him to Number Two.
* AliceAllusion: A subtle one: In the human chess game at the beginning of the episode, Number Six is the white queen's pawn--the same position as Alice in ''Literature/ThroughTheLookingGlass''.
* ArmorPiercingQuestion: Six's methodology for finding out who is a guard and who is a prisoner.
* BavarianFireDrill: Number Six impersonates a guard simply by acting imperious. The other prisoners, who have been conditioned to be subservient, buy it without question.
* BecomingTheMask: This is probably why "Checkmate" represents Six's darkest hour. Not only did he fail utterly at his plan, he did so because he proved he would be an incredibly effective jailer in his own right, having inadvertently convinced the other prisoners he already is one.
* BrainwashedAndCrazy: The Queen is brainwashed into believing she's in love with Six in order to make her spy on him.
* TheBusCameBack: The shopkeeper from "Arrival" makes a return appearance, one of the few Village residents to do so. His behaviour during Number 6's test confirms he's a prisoner and not a warden.
* {{Foreshadowing}}: Six tests the behaviour of other Villagers to see who's a prisoner and who's a warden. But his method of questioning convinces the other prisoners that ''he'' is a warden [[spoiler:and a possible early clue that Number Six will turn out to be Number One.]]
* HoistByHisOwnPetard: Six actually screws himself in this episode as his entire strategy is based around most people not being as unbreakable as himself. So the fact he is unbreakable means his collaborators decide he's one of the guards.
* HumanChess: Unlike other examples of this trope the players are volunteers, but one of them, portraying a Rook, is taken to the hospital for '[[{{brainwashing}} treatment]]' when [[TheEvilsOfFreeWill he makes a move on his own initiative]].
--->'''Number 6:''' Who's he?
--->'''Number 8 (The White Queen):''' He's the champion.
--->'''Number 6:''' Who was he?
--->'''Number 8:''' [[UnPerson Hard to say.]] I've heard rumors.
--->'''Number 6:''' Such as?
--->'''Number 8:''' That he's an ex-count. They say that his ancestors used to play using their retainers as chess pieces. They say they were beheaded as they were wiped from the board. Oh, don't worry; it's not allowed here.
** Later Number Six has a quiet word with the ex-count.
--->'''Number 6:''' So, why do you use people?
--->'''Count:''' Because I can. I would say it [[HowTheMightyHaveFallen satisfies the desire for power]]. [[GildedCage It's the only opportunity one gets here.]]
* RuleOfSymbolism: In the chess game both sides are dressed the same. Apart from the implied NotSoDifferentRemark about both sides in the UsefulNotes/ColdWar, there's also the fact that you can't tell the difference between the prisoners and the guards in the Village. The ex-count says he can tell the difference by "the moves that they make". Number Six puts this into practise with his SpotTheImposter test.
* SpotTheImposter: The prisoners can't band together to escape the Village because no-one knows who is a guard posing as a prisoner. Number Six is able to identify the guards by detecting their subconscious arrogance (e.g. by asking for help with a simple task, the guard would abruptly tell him to do it himself and walk off). Thus he's able to assemble a team of genuine prisoners from the remainder.

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