The time-traveling Doctor (Tom Baker) and the newly regenerated Romana (Lalla Ward) arrive on a rocky, inhospitable planet to investigate evidence of deep underground drilling only to find an old enemy -- the alien race the Daleks -- firmly ensconced. Now, the Doctor must find the Daleks' creator -- the evil scientist Davros (David Gooderson) -- before the Daleks do to prevent an escalation in their war against the Movellans.