On the eve of May Day, dark elemental forces begin to disturb the village of Devil's End as the Master summons the demon Azal: unexplained murders, a stone gargoyle come to life, and a nigh-impenetrable infernal energy dome. With the Master fully prepared to destroy the Earth, the Doctor and UNIT - aided by a benevolent practitioner of witchcraft - battle the wicked rites of a secret science wielded by an alien from another world.
as The Doctor
as Jo Grant
as Brigadier Lethbridge-Stewart
as Captain Mike Yates
as Sergeant Benton
as The Master
as Azal
as Bok
as Miss Hawthorne
as Bert the Landlord
as Winstanley
as Prof. Horner
as Alastair Fergus
as Harry
as Garvin
as Dr. Reeves
as Tom Girton
as PC Groom
as Baker's Man
as Sgt. Osgood
as Thorpe
as Jones