Fabula
Object
Object

Cybermen's Chest Unit Plastic

Abstract material property of Cybermen's chest units, identified as a structural weakness during the sickbay debate. Serves as the theoretical basis for Polly's acetone test, not a physical object.
4 appearances

Purpose

Covers vital components in Cybermen's chest units, vulnerable to solvents like acetone

Significance

Sparks Polly's acetone weapon idea, the 'Polly cocktail,' which gives companions a tactical edge against Cybermen dominance

Appearances in the Narrative

When this object appears and how it's used

4 moments
S4E25 · The Moonbase Part 3
Jamie’s remark sparks solvent solution

The plastic in the Cybermen’s chest units is identified by Polly as a critical vulnerability. She notes that nail varnish (a plastic) can be dissolved by acetone (nail varnish remover), leading her to hypothesize that the same principle could apply to the Cybermen’s armor. This object is central to the companions’ strategic discussion, as it represents the weak point in an otherwise formidable enemy. The plastic’s composition becomes the key to unlocking a solution, transforming an abstract threat (the Cybermen) into a tangible problem with a potential chemical remedy. Its mention shifts the group’s focus from radiation to a more accessible and immediate countermeasure.

Before: The plastic in the Cybermen’s chest units is known to the companions but has not been considered as a target for exploitation. Its vulnerability to solvents like acetone is not yet recognized.
After: The plastic is now understood as a critical weakness that can be exploited. Polly’s hypothesis positions it as the primary focus for the companions’ next steps, setting the stage for the development of the 'Polly cocktail.'
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S4E25 · The Moonbase Part 3
Polly deduces Cybermen’s solvent weakness

The Cybermen’s chest units, made of a plastic-like material, are identified by Polly as a critical vulnerability. She deduces that acetone (nail varnish remover) can dissolve this plastic, offering a way to disable or destroy the Cybermen. This object is central to the companions’ strategy, as its weakness provides the foundation for their counterattack. The discussion about its composition shifts the group’s focus from radiation (Gravitron) to chemical solvents, marking a turning point in their planning.

Before: Intact and functional on the Cybermen, housing their vital organs and cybernetic components.
After: Identified as a target for acetone-based dissolution, pending experimental validation.
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S4E25 · The Moonbase Part 3
Companions disrupt Cybermen with solvent attack

The Cybermen's Chest Units are the primary targets of the 'Polly cocktail' ambush. Ben, Jamie, and Polly spray the solvent mixture directly at these vulnerable plastic components, causing them to bubble, corrode, and dissolve instantly. The chest units, which house the Cybermen's critical circuitry, fail catastrophically under the chemical assault, leading to the immediate collapse of Cyberman 1 and Cyberman 2. This direct attack on their mechanical vulnerability proves decisive in disrupting their control over the moonbase.

Before: Intact and functional, housing the Cybermen's critical circuitry and providing them with mechanical resilience.
After: Corroded, dissolved, and non-functional, leading to the immediate shutdown of the Cybermen targeted.
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S4E25 · The Moonbase Part 3
Hobson prioritizes Gravitron over fallen crew

The Cybermen's chest units, though already dissolved by the 'Polly cocktail' before this event begins, are referenced indirectly as the reason the Cybermen are incapacitated. Their vulnerability to the acetone-based solvent is a key tactical advantage for the companions, and their defeat sets the stage for Hobson's utilitarian priorities to take center stage. The dissolved chest units symbolize the fragility of the Cybermen's collective, even as their lingering influence is felt through the mind-controlled crewmen.

Before: Intact and functional, protecting the Cybermen's internal systems. Cyberman 1 and Cyberman 2 are still operational at the start of the broader scene but are dissolved by the 'Polly cocktail' before this event.
After: Dissolved and non-functional, rendering the Cybermen incapacitated. The companions' weapon has proven effective, but the moral aftermath of their victory is now in focus.
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