William Hartnell is the Doctor in this original television soundtrack adventure, presented here with linking narration by a member of the original cast.

The TARDIS arrives on a vast spaceship in the distant future, and the Doctor, Steven, and Dodo meet the only survivors from the planet Earth. They are on a 700 year voyage to the planet Refusis II, in the company of their mute, one-eyed servants the Monoids. Dodo unwittingly spreads her cold amongst the Monoids, and it proves deadly to them. The Doctor provides a cure, and they leave, but the TARDIS jumps forward in time, taking its occupants to the Ark's future. There the Doctor and his friends are horrifed to discover that the balance of power has shifted, and that humanity is now enslaved by the Monoid race.

This release also includes an interview with the linking narrator.