Ben prepares solvent weapon for vacuum

In the Control Room, Ben urgently dismantles a fire extinguisher to repurpose its glass cylinder as a delivery system for Polly’s acetone-based solvent—a weapon proven effective against Cybermen. When Polly questions why he can’t simply spray the solvent, Ben explains the vacuum of space would cause it to evaporate before impact, forcing him to manually carry the cylinder outside. His decisive action reveals his growing willingness to take extreme risks, particularly when a companion’s life is at stake. The scene underscores the desperation of the moonbase’s defense, where untested tactics must be attempted immediately to counter the Cybermen’s relentless advance. Ben’s departure into the airlock marks a turning point: the group’s survival now hinges on exploiting the Cybermen’s chemical vulnerability in the harsh lunar environment, a gamble that could either save Benoit or doom them both.

Plot Beats

The narrative micro-steps within this event

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Polly questions Ben's plan as he prepares a fire extinguisher, but Ben clarifies that the solvent would evaporate in the vacuum. He then rushes out with a cylinder of the solvent mix, while Benoit is pursued outside by a Cyberman.

questioning to urgency

Who Was There

Characters present in this moment

4

Urgent and determined, with an undercurrent of protective fury. His frustration with the constraints of the environment (the vacuum) is tempered by his focus on the mission—saving Benoit. There’s no hesitation, only action.

Ben Jackson is in a state of urgent, focused action, dismantling a fire extinguisher with practiced efficiency. His hands move quickly, driven by the immediate threat to Benoit’s life outside. He explains the vacuum’s effect on the solvent to Polly with a mix of impatience and authority, his voice sharp but not unkind. Physically, he is already halfway out of the Control Room, his body language tense and decisive as he prepares to suit up for the lunar surface. His actions reveal a man who has transitioned from skeptic to leader, taking calculated risks when his companions are in danger.

Goals in this moment
  • Deliver the solvent to the Cyberman chasing Benoit before it’s too late
  • Protect Benoit and ensure his survival by exploiting the Cybermen’s weakness
Active beliefs
  • The solvent is the only viable weapon against the Cybermen in this environment
  • Every second counts—delay could mean Benoit’s death
Character traits
Resourceful under pressure Protective of companions Decisive in crises Practical thinker Willing to take extreme risks for others
Follow Ben Jackson's journey

None (Cybermen lack emotions), but its actions convey a sense of inevitable doom. It is a force of destruction, indifferent to Benoit’s plight, and its pursuit underscores the urgency of Ben’s mission.

The Cyberman is not physically present in the Control Room but is the immediate, looming threat outside. It is chasing Benoit on the lunar surface, gaining on him with relentless efficiency. Its presence is implied through Ben’s urgency and the off-screen action—it represents the cold, mechanical danger that the moonbase crew must counter. The Cyberman’s role here is as the antagonist driving the conflict, its actions forcing Ben into a high-risk maneuver.

Goals in this moment
  • Capture or convert Benoit to expand the Cybermen’s ranks
  • Prevent any interference with the Cybermen’s plan to control Earth’s weather
Active beliefs
  • All organic life is inferior and must be assimilated or eliminated
  • The moonbase is a strategic target that must be secured
Character traits
Relentless and single-minded in pursuit Mechanically efficient (gaining on Benoit without hesitation) A symbol of the dehumanizing threat to the moonbase crew
Follow Cybermen (Collective)'s journey

Desperate and fearful, but still clinging to hope that the moonbase crew can save him. His emotional state is inferred from the urgency of the situation—he is running for his life, and his survival hinges on Ben’s success.

Roger Benoit is not physically present in the Control Room during this event, but his plight is the catalyst for Ben’s actions. Off-screen, Benoit is being chased by a Cyberman on the lunar surface, his desperation implied by the urgency of Ben’s movements. His approach to the airlock entry door is a critical detail—it signals that he is running out of time and options. Though unseen, his presence looms large over the scene, driving the stakes of Ben’s gamble.

Goals in this moment
  • Reach the airlock and re-enter the moonbase safely
  • Survive the Cyberman’s pursuit long enough for Ben to intervene
Active beliefs
  • The moonbase crew will find a way to help him (as evidenced by his approach to the airlock)
  • The Cybermen are an existential threat that must be stopped at all costs
Character traits
Vulnerable and desperate (implied by the Cyberman chase) Dependent on the moonbase crew for survival Dutiful even in crisis (approaching the airlock suggests he’s trying to re-enter safely)
Follow Roger Benoit's journey
Supporting 1

Confused but engaged, with a hint of frustration at not immediately grasping the solution. Her emotional state is secondary to Ben’s in this moment, but her curiosity drives her to ask questions that could refine their approach.

Polly Wright stands beside Ben, her confusion evident as she questions his method of delivering the solvent. She is physically present in the Control Room but not yet fully engaged in the action, her role here more reactive than proactive. Her dialogue reveals her scientific mind grappling with the practical limitations of the environment, and her concern for Benoit is implicit in her tone. Though she doesn’t yet understand the full stakes, her presence underscores the collaborative nature of the group’s efforts.

Goals in this moment
  • Understand why the solvent can’t be sprayed directly at the Cybermen
  • Support Ben’s plan, even if she doesn’t fully comprehend it yet
Active beliefs
  • The solvent’s effectiveness is proven, but its delivery method must account for the lunar environment
  • Ben’s experience and quick thinking are reliable in crises
Character traits
Quick to question and seek understanding Scientifically curious Protective of the group (though not yet fully aware of the immediate threat to Benoit) Adaptive thinker
Follow Polly Wright's journey

Objects Involved

Significant items in this scene

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Acetone Solvent Cylinder (Polly's Formula)

Polly’s acetone-based solvent is the moonbase crew’s only known weapon against the Cybermen. Ben fills the glass cylinder with this corrosive liquid, which will dissolve the Cyberman’s chest unit upon impact. The solvent’s effectiveness is proven, but its delivery is the challenge—it cannot be sprayed in the vacuum, so it must be carried manually. This object is the heart of the plan, the one thing that can turn the tide against the Cybermen. Its presence in the scene underscores the high stakes: without it, the Cybermen would be unstoppable, and Earth would be doomed. The solvent’s role is both a scientific solution and a narrative lifeline, representing hope in the face of overwhelming odds.

Before: Stored in the Control Room, ready for use …
After: Sealed inside the glass cylinder, carried by Ben …
Before: Stored in the Control Room, ready for use but not yet deployed. It is a clear liquid, its potency known but its delivery method still uncertain until Ben’s improvisation.
After: Sealed inside the glass cylinder, carried by Ben into the lunar vacuum. Its fate is now tied to the cylinder’s survival—if it reaches the Cyberman, it will save Benoit; if not, the Cybermen’s plan will proceed unchecked.
Moonbase Sickbay Fire Extinguishers (Repurposed as Solvent Weapon)

The fire extinguishers in the Control Room are repurposed as the critical component in Ben’s improvised weapon. Ben dismantles one, removing its glass cylinder to use as a container for Polly’s acetone-based solvent. This object transitions from a mundane safety tool to a lifeline in the fight against the Cybermen. Its sturdy construction and pressurized design make it ideal for holding the solvent, and its removal from the extinguisher is a symbolic act—turning safety equipment into a weapon of desperation. The fire extinguisher’s involvement highlights the moonbase crew’s resourcefulness in the face of overwhelming odds.

Before: A standard red metal fire extinguisher mounted on …
After: Dismantled, with its glass cylinder removed and repurposed …
Before: A standard red metal fire extinguisher mounted on the wall of the Control Room, fully functional and unused until this moment. It is part of the moonbase’s safety equipment, designed for fires but now being repurposed for a far deadlier purpose.
After: Dismantled, with its glass cylinder removed and repurposed as a solvent container. The remaining parts of the extinguisher are left behind in the Control Room, now useless for their original purpose but having served a new, critical role in the battle against the Cybermen.

Location Details

Places and their significance in this event

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Lunar Surface (Moonbase Perimeter)

The lunar surface is the battleground where Benoit’s life hangs in the balance. It is a barren, airless expanse, where the Cyberman chases Benoit with relentless efficiency. The surface is also where Ben must venture to deliver the solvent, stepping out of the airlock and into the deadly vacuum. This location is defined by its harshness—low gravity, extreme temperatures, and the ever-present threat of exposure. It is a place of isolation and danger, where every move must be calculated. The lunar surface’s role in this event is to amplify the stakes: Ben’s mission is not just about saving Benoit, but about surviving the environment itself.

Atmosphere Harsh and unforgiving, with a sense of isolation and danger. The vast emptiness of the …
Function Battleground where Benoit is being chased by the Cyberman and where Ben must deliver the …
Symbolism Represents the final frontier of the moonbase’s defense. It is a place where the crew’s …
Access Restricted to those in spacesuits. The vacuum of space makes unprotected exposure fatal, and the …
The barren, dusty regolith of the lunar surface, stretching endlessly under the stark light of Earth’s reflection The low gravity, making movement feel weightless and precarious The silence of the vacuum, broken only by the sound of Ben’s breathing in his spacesuit The distant figure of Benoit, running for his life with the Cyberman gaining on him
Moonbase Airlock

The airlock is the threshold between life and death, the final barrier Ben must cross to reach the lunar surface. It is a pressurized chamber where he dons his spacesuit, the last safe space before stepping into the vacuum. The airlock’s role in this event is critical—it is the point of no return, where Ben commits to his high-risk mission. The hiss of the seal and the diagnostic beeps create a sense of urgency, as if the airlock itself is counting down to the moment Ben must act. This location is a symbol of transition, where the safety of the moonbase ends and the dangers of the lunar surface begin.

Atmosphere Sterile and urgent, with a sense of impending action. The airlock’s confined space amplifies the …
Function Transition point between the moonbase and the lunar surface. It is where Ben equips himself …
Symbolism Represents the boundary between safety and danger, between the known and the unknown. The airlock …
Access Restricted to authorized personnel with proper training and equipment. The airlock’s systems are designed to …
The stark overhead lights casting a clinical glow over the chamber The hiss of the seal as the airlock pressurizes, a sound of finality The diagnostic beeps of the system, counting down to Ben’s departure The bulky spacesuit hanging on the wall, ready for Ben to don
Moonbase Control Center

The Control Room is the nerve center of the moonbase, where the crew coordinates their defense against the Cybermen. In this event, it serves as the staging ground for Ben’s desperate plan. The room is filled with tension, its consoles humming with activity as the crew works to counter the Cybermen’s threat. Ben’s dismantling of the fire extinguisher and his hurried explanation to Polly take place here, making the Control Room a space of both urgency and improvisation. It is a place of last resorts, where mundane objects like fire extinguishers are repurposed as weapons. The room’s atmosphere is one of controlled chaos, with the weight of the mission pressing down on everyone present.

Atmosphere Tense and urgent, with a sense of impending doom. The air is thick with the …
Function Staging ground for Ben’s improvised weapon and the launch point for his mission to save …
Symbolism Represents the moonbase crew’s resourcefulness and desperation. It is a place where the ordinary (fire …
Access Restricted to authorized moonbase personnel during the crisis. The Cybermen have not yet breached this …
The hum of consoles and equipment, creating a backdrop of urgency The clatter of Ben dismantling the fire extinguisher, a sound of improvisation The stark overhead lights casting sharp shadows, emphasizing the tension in the room The presence of fire extinguishers and other safety equipment, now being repurposed for combat

Narrative Connections

How this event relates to others in the story

What this causes 1

"Ben prepares to fight the Cybermen in an environment that renders their technology ineffective, explaining why he needs a solvent."

Ben’s solvent attack on a Cyberman
S4E25 · The Moonbase Part 3

Key Dialogue

"POLLY: Why can't you squirt it at them like you did just now?"
"BEN: Because duchess, it would evaporate in the vacuum before it hits them. There, now come on."