Object
Citadel Security Beam Trap
A concealed photoelectric beam system spanning the Citadel's entrance and corridors, composed of sensor cells that detect movement interruptions. When triggered—by Jamie breaking a beam during an unauthorized search or Zoe stumbling into its path—the system emits a shrill alarm, locks compartments to contain intruders, and summons robotic search parties (White Robots) and human security forces (e.g., Gulliver). The activation isolates intruders from allies (e.g., the Doctor and Zoe) and escalates the threat level. The system is part of the Citadel's layered defense, designed to detect unauthorized movement and deploy countermeasures such as heavy grills or robotic pursuers.
4 appearances
Purpose
Detects intruders by interruption to trigger alarms and deploy locking grill
Significance
Imprisons Jamie right after his discovery of the Doctor's failed test report, spiking his paranoia during the Gulliver confrontation and exposing the Citadel's ruthless security under the Master's grip
Appearances in the Narrative
When this object appears and how it's used