The TARDIS has been stolen from Gatwick Airport, and the Doctor and Jamie are hot on its trail. A series of cryptic clues lead them to an antiques shop owned by Edward Waterfield, and there it becomes clear that an elaborate trap has been laid for them; but by whom, and for what purpose? Only a journey back in time to the 1860s will reveal the answer...

The Daleks are in search of the Human Factor, something which they believe will help their quest for universal domination. In order to achieve their aim they need the Doctor's help, and the use of his TARDIS.

The Daleks' plan has far-reaching consequences, leading to conflict and destruction of astonishing proportions.

Frazer Hines, who plays Jamie in the story, narrates this classic story from 1967, of which all but one episode is now missing from the television archives.