The Doctor's Notebook (TARDIS Key Codes & Travel Logs)

The Doctor’s notebook is the most critical object lost during the ambush. Susan’s panic over its absence reveals its importance: it contains the TARDIS’s key codes and travel logs, making it essential for their return home. The notebook’s disappearance drives the companions’ urgency to find the Doctor, as its loss could strand them permanently. Its absence foreshadows the tribe’s later use of the Doctor’s technology as a power tool, raising the stakes for the group’s survival and escape.

The Doctor’s notebook is the most critical object in this event, as its abandonment signals a catastrophic turn of events. Containing the TARDIS’s key codes and travel logs, the notebook is irreplaceable and its loss threatens the companions’ ability to return home. Susan’s panic over its disappearance drives the group’s urgency, making the notebook the linchpin of their immediate goals and the emotional core of this moment.