Underworld The quest is the quest... On the very edge of the universe, the TARDIS lands on an ancient spaceship. The ship's crew members are from the destroyed world of Minyos, and are on a centuries-long mission to retrieve the race banks that could restore their people to life. The Invasion of Time The Doctor allies himself with the Vardans and paves the way for an invasion of the Time Lord homeworld, Gallifrey. Leela joins forces with the Outsiders to repel the invaders, but the Vardans are only the puppets of a far greater threat - the Sontarans! The Ribos Operation The Doctor is summoned by the White Guardian, and tasked with finding the six segments of the Key to Time. Together with his new Time Lady companion, Romana, the Doctor travels to the feudal world of Ribos, in pursuit of the first segment.