The Doctor is saved from the stoning in the nick of time and taken to see the Immortal who wants to use the Doctors far greater knowledge to his advantage. Meanwhile, Peri is taken before Queen Katryca of the local tribe and told that she is to become part of the tribe and take many husbands because there is a shortage of women.

Queen Katryca and the rest of the tribesmen arrive at the underground bunker where they confront Drathro The Immortal one. The Doctor tries to convince Drathro that he will repair the Black Light system while he fears that a possible upcoming explosion of the system could have the potential to destroy the universe.