Laylora - the Paradise Planet. A world of breath-taking beauty, where the peace-loving inhabitants live in harmony with their environment. Or do they? The Doctor and Rose arrive to find that the once perfect eco-system is showing signs of failing. The Paradise has become a death trap as terrifying creatures from ancient legends appear and stalk the land.

Is there a connection between the human explorers who have crash-landed and the savage monsters? And what price might one human have to pay to save the only home he has ever known?

The Doctor and Rose are in a race against time to find a cure for a sick planet.