Object
Master's Cell Sash Window Pane
Part of the Master's confinement cell in the Royal Palace service passage, used exclusively for silent signaling between confined parties.
1 appearances
Purpose
Controlled view and limited ventilation for the prisoner within restricted confines
Significance
Becomes a critical channel for secret communication that coordinates the escape plan; the window's glass transmits coded gestures between Jo and the Doctor at a moment when verbal signals would risk detection by unseen surveillance
Appearances in the Narrative
When this object appears and how it's used