Set in ancient mexico, this lavish 1970s children’s series about a young boy’s battle against evil stars doctor who's patrick troughton as a bloodthirsty priest with diane keen as a toltec princess. All 12 episodes of the lavish 1970s children’s series set in ancient mexico, starring patrick ‘doctor who’ troughton as a bloodthirsty toltec priest who demands human sacrifices to satisfy his god. Only by marrying emperor’s daughter chimalma diane keen can prince heumac ensure the return of the peaceful god quala – the feathered serpent – so he sends servant boy tozo to ask for her hand. Soon, though, tozo is embroiled in a terrible battle between good and evil.