by Hal Erickson
synopsis
In the conclusion of the four-part story "The Keeper of Traken," the Melkur (Anthony Ainley) has revealed himself to be the Doctor's perennial nemesis, the renegade Time Lord, the Master. the Doctor (Tom Baker) and Adric (Matthew Waterhouse) must prevent the Master from becoming the new Keeper of the Union of Traken, a contingency that would result in disaster and devastation throughout the universe. Sarah Sutton joins the cast as the Doctor's new companion, Nyssa. Written by Johnny Byrne, "The Keeper of Traken, Episode 4" originally aired on February 21, 1981.
