The Point of Stillness. A place the Time Lords are forbidden to go. It cannot be drawn, it cannot be whispered, it cannot be thought. And yet somebody is very keen to reach it.
Deep within the TARDIS, something unusual is happening. One of the ship's oldest secrets is about to be revealed, and once it is, nothing will ever be the same again.
As danger materialises deep within the ship, spectral strangers lurk in the corridors and bizarre events flood the rooms, someone long-forgotten is ready to reappear. The Doctor and Leela are soon to discover that their home isn't quite the safe stronghold they thought.