Doctor tests alien communication device

In the underground laboratory, the Doctor and Liz Shaw activate a jury-rigged communication device to establish contact with the captive alien ambassadors, hoping to expose General Carrington’s fabricated invasion. The Doctor, feigning compliance with Carrington’s scheme, uses a modified Morse code signal to transmit a message, while Liz monitors for any response. Their urgency is palpable—this is a desperate attempt to reach the aliens before Carrington’s staged attack escalates into full-scale war. The Doctor’s reliance on Liz’s technical oversight underscores their partnership, while the lack of immediate reaction from the observation room hints at deeper deception or the possibility that the aliens are being actively suppressed. The scene underscores the Doctor’s strategic patience and Liz’s growing trust in his methods, even as the stakes rise. The failure of the first transmission foreshadows the need for more drastic measures, setting up the Doctor’s eventual SOS signal to UNIT—a critical turning point in the story.

Plot Beats

The narrative micro-steps within this event

2

The Doctor and Liz prepare a communication device in the underground laboratory. The Doctor instructs Liz to switch on the power to test the device and then begins sending a signal.

hopeful to uncertain

Liz monitors for any reaction to the Doctor's signal. When Liz reports no reaction yet, the Doctor indicates that they will continue attempting contact, gesturing to Masters to watch the observation room as he continues sending his message.

uncertain to determined

Who Was There

Characters present in this moment

3

Anxious but resolute; her scientific rigor is tempered by the high stakes of their mission, and she trusts the Doctor’s leadership despite her concerns.

Liz Shaw activates the power to the jury-rigged communication device, her fingers moving with scientific precision as she monitors the equipment for any response. She stands nearby, her eyes fixed on the readouts, her posture tense but focused. When the Doctor asks if the signal is strong enough, she voices her concern in a hushed tone, revealing her anxiety about the plan’s success. Despite her apprehension, she remains determined to assist the Doctor, her technical expertise and loyalty to UNIT driving her actions in this critical moment.

Goals in this moment
  • Ensure the jury-rigged communication device functions correctly and reaches the alien ambassadors.
  • Monitor for any reactions or responses from the aliens to assess the signal’s effectiveness and gather intelligence.
Active beliefs
  • The Doctor’s plan is their best chance to expose Carrington’s deception and prevent war.
  • Her technical oversight is crucial to the success of their covert operation.
Character traits
Anxious but determined Technically precise and methodical Loyal to the Doctor and UNIT’s mission Voices ethical concerns and practical doubts Resourceful under pressure
Follow Elizabeth Shaw …'s journey

Feigned calm masking deep urgency and strategic focus; determined to expose Carrington’s deception before it escalates into war.

The Doctor finishes assembling the jury-rigged communication console with precise, deliberate movements, his focus unwavering. He activates the device and transmits a modified Morse code signal—di di di dah dah dah di di di—while directing Liz to monitor for reactions and gesturing to Masters to observe the observation room. His calm demeanor masks the urgency of their situation, as he feigns compliance with Carrington’s scheme while secretly working to expose the deception. The Doctor’s strategic patience and improvisational genius are on full display, as he balances risk and subtlety in this high-stakes gambit.

Goals in this moment
  • Establish covert communication with the captive alien ambassadors to expose Carrington’s fabricated invasion.
  • Gather intelligence on the aliens' status and reactions to assess the next steps in thwarting Carrington’s plan.
Active beliefs
  • Carrington’s staged invasion must be exposed to prevent interstellar conflict.
  • The alien ambassadors are key to revealing the truth and can be trusted as allies.
Character traits
Strategic and improvisational Calm under pressure Manipulative (in a constructive sense) Empathetic toward oppressed aliens Feigns compliance to outmaneuver antagonists
Follow The Third …'s journey
Supporting 1

Obedient and detached; his loyalty to Carrington blinds him to the Doctor’s true intentions, making him a passive but critical participant in the scene.

Masters, Carrington’s enforcer, stands in the observation room as directed by the Doctor, his gaze fixed on the monitoring equipment. He watches for any reactions—human or alien—to the Morse code signal, his presence a silent but watchful force in the room. Though he is loyal to Carrington, the Doctor’s subtle manipulation places him in a position where he unwittingly aids their covert efforts, adding an layer of tension to the scene as the Doctor tests the limits of Masters’ obedience.

Goals in this moment
  • Follow the Doctor’s instructions to monitor the observation room for reactions.
  • Report any unusual activity to Carrington, though he remains unaware of the Doctor’s true motives.
Active beliefs
  • His role is to enforce Carrington’s orders without question.
  • The Doctor’s actions are merely part of Carrington’s plan, and thus require no deeper scrutiny.
Character traits
Loyal to Carrington’s authority Obedient to directives (even those subtly influenced by the Doctor) Silent and observant Unwittingly complicit in the Doctor’s plan
Follow Masters (Reegan’s …'s journey

Objects Involved

Significant items in this scene

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Doctor and Liz Shaw's Jury-Rigged Alien Communication Console (Carrington's Underground Laboratory)

The jury-rigged communication device is the linchpin of the Doctor and Liz’s covert operation. Assembled hastily in the underground laboratory, it serves as their sole means of contacting the captive alien ambassadors without alerting Carrington’s forces. The Doctor activates the device, and its flashing lights indicate the transmission of the modified Morse code signal—di di di dah dah dah di di di—a sequence designed to evade detection while reaching the aliens. Liz monitors the device’s readouts, her technical oversight ensuring the signal’s integrity, though its failure to elicit an immediate response underscores the urgency of their mission. The device’s jury-rigged nature reflects the desperation of their situation, as they improvise solutions in the face of Carrington’s deceptive scheme.

Before: Assembled but inactive; the Doctor has just finished …
After: Active but unresponded to; the Morse code signal …
Before: Assembled but inactive; the Doctor has just finished constructing it, and Liz is preparing to power it on.
After: Active but unresponded to; the Morse code signal has been transmitted, but no reaction has been detected from the aliens or the observation room.
Doctor’s Jury-Rigged Morse Code Signal (Underground Lab Transmission)

The Doctor’s modified Morse code signal—di di di dah dah dah di di di—is the covert message transmitted via the jury-rigged communication device. Designed to be subtle yet effective, it is intended to reach the captive alien ambassadors without alerting Carrington’s forces. The signal’s failure to provoke an immediate response adds tension to the scene, as the Doctor and Liz are left wondering whether the aliens are being actively suppressed or if the signal simply wasn’t strong enough. This moment foreshadows the need for more drastic measures, setting the stage for the Doctor’s eventual SOS signal to UNIT.

Before: Untransmitted; the Doctor has prepared the sequence but …
After: Transmitted but unacknowledged; the signal has been sent, …
Before: Untransmitted; the Doctor has prepared the sequence but has not yet activated the device.
After: Transmitted but unacknowledged; the signal has been sent, but no response has been detected from the aliens or the observation room.
Underground Laboratory Observation Room

The observation room in the underground laboratory serves as a critical monitoring hub during this event. Masters, under the Doctor’s direction, watches the room’s equipment for any reactions—human or alien—to the Morse code signal. The room’s sterile, confined space amplifies the tension, as the Doctor and Liz await any sign that their covert communication attempt has been successful. The observation room’s role as a surveillance point highlights the power dynamics at play, with Carrington’s forces unknowingly aiding the Doctor’s efforts to expose the truth.

Before: Monitoring equipment is active, but no unusual activity …
After: Monitoring equipment remains active, but no reactions or …
Before: Monitoring equipment is active, but no unusual activity has been detected prior to the signal transmission.
After: Monitoring equipment remains active, but no reactions or responses are observed following the Morse code transmission.

Location Details

Places and their significance in this event

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Underground Laboratory

The underground laboratory is a sterile, confined space filled with humming test equipment and the tension of covert operations. It serves as the primary setting for the Doctor and Liz’s desperate attempt to contact the alien ambassadors, its isolated nature providing the secrecy they need to execute their plan. The laboratory’s sterile walls and locked vaults symbolize the oppression of Carrington’s regime, as the Doctor and Liz work against the clock to expose the deception before it escalates into war. The atmosphere is one of urgency and quiet determination, with every exchange between the characters charged with the weight of their mission.

Atmosphere Tense and urgent, with whispered conversations and the hum of equipment creating a sense of …
Function Hidden workspace for covert operations; a place where the Doctor and Liz can improvise solutions …
Symbolism Represents the oppression of Carrington’s regime and the Doctor’s defiance of flawed authority. The laboratory’s …
Access Restricted to authorized personnel; heavily guarded by Carrington’s forces, with the Doctor and Liz operating …
Sterile, confined walls filled with humming test equipment Locked vaults where the alien ambassadors are held captive Whispered conversations between the Doctor and Liz, underscoring the urgency of their mission The observation room, where Masters monitors for reactions to the Morse code signal

Narrative Connections

How this event relates to others in the story

What this causes 1

"The Doctor and Liz building and testing the communication device(beat_f683303b9758a54c) directly causes the broadcasting of an SOS signal, reaching UNIT Communications ."

UNIT Detects the Doctor’s SOS Signal
S7E18 · The Ambassadors of Death Part …

Key Dialogue

"DOCTOR: All right? LIZ: Mmm hmm. DOCTOR: Right, switch on the power, Liz, will you?"
"LIZ: (sotto) Do you think the signal will be strong enough? DOCTOR: (sotto) Well, I've boosted it as much as I possibly can."
"DOCTOR: Any reaction? LIZ: No, not yet. DOCTOR: Well, we'll just have to keep on trying, won't we."