Adrian Gibbs

The Doctor's latest regeneration has proven more unstable than his previous ones. His two assistants, Tegan and Nyssa, help him recuperate on the tranquil planet of Castrovalva. But are things as peaceful as they seem on Castrovalva? What has happened to Adric? And more importantly, where is the Master? As the Doctor begins to recover he realises that the Master has laid a trap even more intricate than he could have imagined and that he will stop at nothing to gain his revenge over the Doctor.

The Doctor goes to Logopolis to repair the TARDIS' chameleon circuit, not knowing that a shadowy watcher is spying on him. Meanwhile, his old enemy the Master has only recently gained secure longevity by possessing the body of Tremas, and revels in his safety. He has plans of his own for the planet of mathematicians, Logopolis, and a plan that could spell doom for the entire universe. The Master's plan could rock Logopolis, the keystone of all life. Could this mean the unravelling of the causal nexus and the end of the universe itself? The Doctor must pit his wits against the Master in a desperate battle to thwart his plans. But he is aware that this might be a fight which could easily spell the end of his life.

The TARDIS falls through a CVE into E-Space and arrives on the planet Alzarius. There the inhabitants of a crashed starliner and a group of young rebels called the Outlers, led by a boy named Varsh and including his brother Adric, are terrorised by a race of Marshmen who emerge from the marshes at a time known as Mistfall. The Doctor discovers that the starliner's inhabitants are not the descendants of its original crew, as claimed by their leaders, the Deciders, but evolved Marshmen. With the Time Lord's help and encouragement, the starliner is repaired and able to leave the planet.