The Doctor is summoned by the mysterious and powerful White Guardian, and sent on a quest to find the six segments of the Key to Time, which, once assembled, will restore balance to the Universe. Joining the Doctor and K9 is the smart and sassy Romana, a Time Lord fresh from the Academy. Landing on the wintry planet of Ribos to locate the first segment, the TARDIS crew quickly find themselves embroiled in a little local trouble with a pair of conmen and an unstable warlord...

The Doctor is chosen for a quest by The White Guardian to go in search for the six segments to the Key to Time, that have been scattered and sent throughout the time/space continuum. With the Key to Time, The White Guardian will restore balance to the universe. Joined by a young time lady named Romana, The Doctor, Romana and K-9 Mark 2 begin their quest and arrive at their first destination, The medieval Russian like world Ribos, where a conman named Garron bids to sell Ribos to a exiled tyrant known as Graff Vynda K, where Unstoffe, Garron's assistant uncovers Garron's scheme and is unaware he is in possession of the first segment of the Key to Time.

The Doctor contemplates a journey to see an old acquaintance and digs a well. Released in cinemas alongside the 3D double-bill of Dark Water and Death in Heaven.

The Doctor, Jamie and Zoe return to Earth and become embroiled in the schemes of Tobias Vaughn. They meet up with an old friend, Colonel (now Brigadier) Lethbridge-Stewart, and some old enemies, the Cybermen.

The TARDIS returns Tegan to Heathrow Airport: Tall trees, peaceful, clear skies, thriving vegetation and a touch of sulfur in the air. Obviously the TARDIS is a little out of date (about three hundred years or so), but upon looking around the Doctor finds there's more amiss than his navigational controls, all arising after a recent comet crash that was not on Earth's schedule.

The TARDIS crew take up residence near Rome in 64AD, where Ian and Barbara are kidnapped by slave traders, and the Doctor's imitation of Maximus Pettulian sees him taken to the court of Emperor Nero where he inadvertently plays a part in deciding the course of history...

In 17th century England, the Doctor and itinerant thespian Richard Mace uncover a plot by a crew of criminal Terileptils to wipe out humanity.

The TARDIS materialises inside an Aztec tomb. Outside it, the Doctor and his companions soon discover that Mexico in the 15th century is a bloodthirsty and dangerous place... And with Barbara mistaken for a reincarnation of an ancient high priest called Yetaxa, the history teacher thinks that she can put an end to the barbaric human sacrifices once and for all. But can she rewrite history without disastrous consequences?

The Doctor, Steven and Dodo land on an alien world in this animated reconstruction of a lost 1966 Doctor Who adventure. There, they meet two peoples: the cutthroat Savages and civilised Elders, who claim to know all about the Doctor and his travels. Is all as it seems, and will the TARDIS crew come out in one piece if it isn't?

The Time Lords send the Doctor and Jo on a mission to deliver a sealed message pod to an unknown party aboard a Skybase orbiting the planet Solos in the 30th century. They are caught quickly in a power struggle between the cruel Marshal of Solos and the young Solonian Ky over the future of Solos - a future that hinges on the contents of the message.