According to popular legend, the great humanitarian Stewart Ransom founded the Independent Earth Colony of Axista Four in the year 2439, but the truth is not as neat and simple as the legend would suggest…Now, in 2539…The Doctor,  Zoe, and Jamie arrive on Axista Four to find the colony in a state of chaos. A breakaway group of colonists – the Realists – have abandoned Ransom’s ‘Back To Basics’  ideal and is creating a new high-tech settlement. The Loyalists who remain are dwindling in number and are facing extinction. Meanwhile, a space ship from Earth has arrive with the news that 80,000 refugees are about to descend on the planet; the Realists are staging raids on the wreck of the colony ship and in a secret underground bunker mysterious aliens who claim to be the planet’s first colonists are beginning to awake. Who are the doglike aliens who call themselves Tyrenians? What is the secret agenda of the sinister Federal Administrator Greene? And what really happened when the colony ship crash-landed on Axista Four 100 years ago? This adventure features the Second Doctor, Zoe and Jamie and the Seventh Doctor and Ace.