An unnamed planet, the distant future. Arriving in a place that seems oddly familiar, the Doctor finds the savage Sevateem tribe battling to free their captive god, Xoanon, from the Evil One and his Tesh servants. But can the whole situation really be the Doctor's fault?
Quest roles:
Terry Walsh(Crew Member (uncredited)), Leslie Schofield(Calib), Max Faulkner(Corporal Adams), David Garfield(Neeva), Victor Lucas(Andor), Brendan Price(Tomas), Colin Thomas(Sole), Lloyd McGuire(Lugo), Tom Kelly(Vardan)