The TARDIS materialises on a planet where the age of prosperity comes frequently, and precious jewels line the streets like litter. Overseeing the residents is the bombastic Captain, half human and half machine. Lurking in shadows will be the Mentiads, secret cowled numbers who set their sights on certain individuals and claim them for their own.

As the physician, Romana and K9 become entangled in local events they may be caught between the evidently insane Captain and evidently sinister Mentiads. But the physician makes an awful discovery under the surface area of the planet, and realises the real nature from the Captain’s operations.

Soon yet another globe comes under danger in the Captain, one which the Doctor knows well: Earth. Can he have the ability to conserve it from a terrible fate?

John Leeson narrates this basic full-cast TV adventure, written by Douglas Adams (The Hitchhiker’s Information towards the Galaxy), and in a particular reward interview he recalls his period as the Tone of voice of K9 in the BBC Television series.