Harry plays hoaxes on gullible tabloid journalists. But when he gets ambitious and tries to sell the faked memoirs of a contract killer to a publisher, things start to go seriously wrong.
When the ailing husband of an adulterous wife is discovered bludgeoned to death and suspicions fall on the older woman's young lover, the newly widowed woman claims that it was she who was solely responsible for the death despite evidence that points to the contrary in this dramatic account of true-life 1935 trial that shocked all of England. Though notable evidence and strong suspicion suggests that the murder may have been of crime of passion perpetrated by the jealous lover only half her age, Alma Rattenbury (Helen Mirren) confesses to the murder of her husband and is soon brought to trial. Despite the fact that Alma is already being deemed guilty by the general public for her adulterous indiscretion alone, her lawyer, star attorney T.J. O'Connor (David Suchet), remains convinced that his client will eventually be cleared of all charges.
When a mystery illness infects the pigs of a village farmer and a local boy is also taken ill, the villagers try to convince a veterinarian that it is caused by a curse from a woman they believe to be a witch.
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.
UNIT is providing security cover at an experimental drilling project at Eastchester, designed to penetrate the Earth's crust and release a previously untapped source of energy. Soon, however, the drill head starts to leak an oily green liquid that transforms those who touch it into vicious primeval creatures with a craving for heat. The Doctor is accidentally transported "sideways in time" by the partially repaired TARDIS control console into a parallel universe where the drilling project is at a more advanced stage. Thwarted by his friends' ruthless alter egos, he works to save both universes.