Summoned to his home world of "Gallifrey" without the company of "Sarah Jane" the "Doctor" (Tom Baker) finds himself arrested and embroiled in the assassination of the President of the High Council. Doomed to a grisly fate, his only option is to announce that he will stand for the office himself. Luckily, the savvy "Castallan" (George Pravda) has some doubts as to the neatness of this whole affair and so they set about using the very limited time available to try and find out just who is pulling the strings that could decimate their planet and destroy the Time Lords forever. They soon discover ...