The Doctor and his companions versus the unknown force controlling the Chumblies.

The Doctor, Vicki, and Steven materialize on a planet so eerily silent that its absence of sound becomes the first clue to its unnatural state. The Doctor’s immediate unease—‘Not a …

After returning to the TARDIS following Vicki’s hostage exchange, the Doctor and Steven discover two Chumblies attempting to breach the ship’s exterior with a drill. The Doctor dismisses their threat, …