Turlough and Peri sabotage the gas supply

Turlough and Peri rush into the bunker to sabotage the Master’s ritual by cutting the numismaton gas supply feeding the sacrificial fire. Turlough outlines a desperate plan to disable the right circuits in the facility’s infrastructure, relying on his technical knowledge and the hope that the system still functions despite the chaos outside. Peri voices concern over their limited time and uncertain chances of success, while Turlough emphasizes the necessity of their actions to buy the Doctor and Malkon the few critical minutes needed to rescue him from the Hall of Fire. Their exchange underscores the high stakes and their shared determination to thwart the Master’s plans before Sarn’s energy is irrevocably exploited. key_dialogue: [ PERI: That kid won't hold them off for long. TURLOUGH: The Doctor can help him. We only need a few minutes. PERI: Do you know what you're doing? TURLOUGH: If I can hit the right circuits, if it still works, I think I can cut the gas supply to their sacrificial fire. ]

Plot Beats

The narrative micro-steps within this event

2

Peri and Turlough discuss the urgency of the situation and Turlough's plan to cut the gas supply to the sacrificial fire.

concern to determination ['INT. BUNKER']

Turlough explains his plan to cut the gas supply, detailing the technical aspects and expressing hope it still works.

hope to anxiety ['INT. BUNKER']

Who Was There

Characters present in this moment

2

Feigned confidence masking acute apprehension about the system's viability and the dire consequences of failure

Turlough kneels before the corroded control dais in the bunker, his fingers tracing degraded Trion glyphs as he assesses the numismaton gas system. His voice is steady but layered with underlying tension, betraying the fragility of his improvised plan. He works with the precision of an exile who has navigated alien tech before, yet the weight of impermanence clings to his movements.

Goals in this moment
  • Disable the numismaton gas supply to interrupt the sacrificial fire feeding the Master’s ritual
  • Ensure Peri relays critical information to the Doctor to support his rescue of Malkon
Active beliefs
  • The Master’s control over Kamelion and the sacrificial fire can be broken by cutting the gas supply at its source
  • Every second gained through sabotage could mean the difference between success and irreversible disaster
Character traits
Technical expertise under pressure Strategic thinking Masked vulnerability beneath calculated resolve
Follow Turlough's journey

Reluctant trust tinged with impatience and growing dread as time slips away from their control

Peri stands at Turlough’s side in the cramped bunker, her breathing sharp with anxiety but her defiance cutting through doubt. She challenges Turlough’s plan both to test its soundness and to force a sense of urgency, her tone oscillating between skepticism and reluctant trust in his abilities.

Goals in this moment
  • Impose real-time pressure to ensure Turlough acts with maximum speed and clarity
  • Clarify the risks to justify the urgency of their sabotage to herself and Turlough
Active beliefs
  • The Doctor’s intervention can only succeed if they buy him those critical minutes
  • Turlough’s technical claims are uncertain but their only viable option
Character traits
Defiant skepticism Urgency-driven curiosity Sense of responsibility to translate knowledge into action
Follow Peripugilliam Brown's journey

Objects Involved

Significant items in this scene

2
Sacrificial Flames in the Hall of Fire

The sacrificial fire in the Hall of Fire—though not physically present in the bunker—is the operational target of their sabotage. It is fed by the numismaton gas supply routed through the bunker’s infrastructure. The fire’s destructive potential is central to the Master’s ritual, and disabling its fuel source severs a core component of his power.

Before: An active, consuming force fueled by the numismaton …
After: Likely diminished or extinguished depending on whether the …
Before: An active, consuming force fueled by the numismaton gas supply, threatening to claim the Doctor and Malkon as sacrifices.
After: Likely diminished or extinguished depending on whether the gas supply is successfully cut following Turlough’s sabotage.
Numismaton Gas

The numismaton gas supply valve is targeted by Turlough for disabling through circuit manipulation. Its corroded brass surface and eroded Trion glyphs pose significant obstacles, requiring him to rely on fragmented memory and measured force. The valve’s operational status is uncertain given decades of disuse and the planet’s destabilized energy matrix, yet it remains the linchpin for interrupting the Master’s sacrificial fire.

Before: Mounted in the control bunker’s central dais, showing …
After: Unknown in the script excerpt—remaining status contingent on …
Before: Mounted in the control bunker’s central dais, showing signs of corrosion, mineral condensation, and strain from decades of inactivity and inconsistent maintenance. The valve is intact but its responsiveness to reassembly or reoperation is unknown.
After: Unknown in the script excerpt—remaining status contingent on whether Turlough successfully cuts the gas flow during or after this exchange.

Location Details

Places and their significance in this event

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Trion Volcanic Control Bunker

The Trion Volcanic Control Bunker serves as the operational nexus where Turlough and Peri attempt to reassert control over Sarn’s volatile energy systems. Its claustrophobic ferrocrete chamber amplifies the tension, forcing the pair into close quarters with rusted controls and flickering emergency lighting. The bunker’s decaying infrastructure mirrors the urgency of their task—each moment wasted threatens to ignite irreversible consequences.

Atmosphere Tension-filled and urgent with a metallic undercurrent of desperation, thick with the scent of ozone …
Function Control center for disabling the Master’s primary power source (numismaton gas supply) via ad-hoc technical …
Symbolism Represents humanity’s fragile struggle against entropy and external manipulation, a bastion of hope clinging to …
Low ceiling enforcing a crouched posture Flickering brass valves etched with corroded Trion glyphs Dripping coolant forming glassine stalactites that shatter on metal plates

Narrative Connections

How this event relates to others in the story

What led here 1

"Turlough's initial plan to save the Doctor by cutting the numismaton gas supply directly escalates into a more detailed execution of that plan in the bunker, where he explains the technical specifics and expresses hope in its success. This shows a shift from abstract planning to concrete action."

Master sighted outside the Hall of Fire
S21E17 · Planet of Fire Part 3
What this causes 1

"Turlough's plan to cut the numismaton gas supply in the bunker is the direct cause of the subsequent moment where he accesses the monitor and observes the fire being extinguished. His actions have a tangible, observable effect."

Turlough monitors fire in Sarnian Temple
S21E17 · Planet of Fire Part 3