Charles Wharton visits Anthony Reynard, the recently widowed husband of his sister Janine. In his unsettling Victorian mansion, Reynard tells Wharton that Janine died by falling off a ladder while dusting the mansion’s East Room, breaking her neck.
The Doctor, Romana, Adric and K9 encounter the enslaved time-sensitive Tharils, who lead them to a white void occupied only by the ruins of an old building and a spaceship - a dimension that might be the key to escaping E-Space.
After an encounter with the Master, an airline stewardess named Tegan Jovanka becomes an unwitting stowaway aboard the TARDIS as it travels to the planet Logopolis. There, the Doctor discovers that the Master's interference with the Logopolitans' advanced mathematics has unleashed a wave of entropy which threatens to consume the entire universe.
The Doctor and Romana arrive on the marsh moon of Delta Magna in search of the next segment of the Key to Time. They are caught in the conflict between the native Swampies and the crew of a chemical refinery. The presence of a gun runner complicates matters; to make things worse, the Swampies intend to awaken Kroll, the giant god that lives beneath the swamps.
The final segment of the Key to Time is at the heart of a devastating war between neighbouring planets Atrios and Zeos. The Fourth Doctor discovers that a sinister entity is manipulating events and the cost of obtaining the final segment may be more personal than he imagined.
The Doctor and a newly-regenerated Romana arrive on Skaro to find that the Daleks, locked in a war with the robotic Movellans, have returned to retrieve their buried creator Davros.
The Doctor and Romana follow a distress signal which leads to the jungle planet Chloris, whose ruthless ruler Lady Adrasta harbors a deadly creature in a pit.
A freak accident leaves two dangerously unstable spacecraft locked together, and a horde of monsters unleashed on their passengers.
Romana fancies a proper holiday and convinces the Doctor to visit the leisure planet Argolis, where a takeover by the Argolins' historic enemy is underway.
On the lush planet Tigella, two opposing factions are divided over the usage of the Dodecahedron, an ancient and powerful artefact which provides the entire planet's energy. The Doctor is summoned to arbitrate the conflict, but the power-crazed Meglos intercepts the call and impersonates him in order to steal the Dodecahedron.
A diplomatic couple adopts the son of the devil without knowing it. A remake of the classic horror film of the same name from 1976.
A police detective falls in love with the woman whose murder he's investigating.
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.
Just as Necrón resigns himself to never completing his book, a mysterious mirror arrives at his door, beckoning him. From that night on, inspiration comes to him unannounced, cloaked in mystery. Yet when the mirror has shown him every face he wears, will Necrón find the courage to confront his own demons?
Momo is a young orphan girl who lives in the ruins of an old Roman amphitheater and becomes friends with everybody in the neighborhood. But when a powerful international corporation starts stealing everybody’s time, nobody has any time left for her, let alone their friends or families. Momo, together with Master Hora, the custodian of time, are the only ones who can go up against the time thieves before all is lost forever.
Two siblings begin to develop special talents after they find a mysterious box of toys, and soon their parents and even their teacher are drawn into a strange new world – and find a task ahead of them that is far more important than any of them could imagine.
Charged with genocide by the treacherous Valeyard at his trial, the Doctor receives help from an unlikely source to turn the tide of the High Council's rulings in his favour and reveal the Valeyard as a wrongdoer: the Master. For the Valeyard's own crimes are so atrocious, even the Doctor's archenemy will help him to ensure that the villain won't see the light of day again. Cornered, the Valeyard flees to the Matrix, where he can be the Doctor's judge, jury and executioner...
As evidence for the defense at his ongoing trial, the Doctor presents an adventure from his future when he is travelling with a computer programmer named Mel. Answering a mysterious distress call from the space liner Hyperion III, they find that the passengers aboard include unscrupulous scientists, secret agents, saboteurs, thieves and a murderer. And lurking in the shadows are the Vervoids, the product of sinister botanical experiments, who will stop at nothing to destroy all non-plant life.
As the Doctor's trial continues, evidence is presented showing his most recent adventure, one where he faces an old adversary, Sil. As a scientist conducts his unethical experiments to prolong the life of Sil's boss Kiv, the Doctor's memories of the events begins to return and an unpleasant surprise awaits him.
The Doctor is summoned before the High Council of Time Lords to stand trial for the charges of harmful interference to the course of events during his travels which have threatened the sanctity of the universe. Indignant at these accusations, the Doctor pleads his case to the Inquisitor with the hope that she will see him as a source of hope and goodwill for existence. However, his prosecuting attorney, a sinister Time Lord known simply as the Valeyard, begins a crusade against the Doctor with the motive of framing him as a villainous renegade.