Synchronicity

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 arrives on the unnamed planet of the Gonds, who are ruled and taught in a form of self-perpetuating slavery by the alien Krotons — crystalline beings whose ship, the Dynatrope, crash-landed there thousands of years earlier after being damaged in a space battle. The Krotons are in suspended animation, in a crystalline slurry form, awaiting a time when they can be reconstituted by absorption of mental energy. Periodically, the two most brilliant Gond students are received into the Dynatrope, nominally to become "companions of the Krotons", but in truth to have their mental energy drained, after which they are killed.

The TARDIS lands in a space museum on Earth in the late 21st century, where the Second Doctor, Jamie and Zoe learn that contact has been lost between Earth and the Moon. In this era, instant travel — T-Mat — has revolutionised the Earth. Its people have lost interest in space travel. The Doctor and his companions travel to the Moon in an old-style rocket and reach the Moonbase, control centre for T-Mat, only to find a squad of Ice Warriors have commandeered the base and plan to use the T-Mat network to their advantage.

The TARDIS materialises in Earth's future on a space beacon just before it is attacked by pirates. The travellers find themselves trapped in a sealed section of the beacon. It is blown apart and flown to where the pirates will plunder it of the precious mineral argonite. They witness a conflict between the pirates and the Interstellar Space Corps, led by General Hermack and Major Warne. The ISC are convinced that the pirates' mastermind is an innocent yet eccentric space mining pioneer named Milo Clancey, while their true leader is a man named Caven. Caven has a secret base on the planet Ta. He is assisted by Madeleine Issigri, daughter of Clancey's ex-partner Dom, who - unknown to her - is now his captive. When Madeleine discovers Caven's full treachery, she helps to bring him to justice. The time travellers are given a lift back to the TARDIS by Clancey in his rickety old ship, the LIZ 79.

The Doctor, Jamie and Zoe arrive on an unnamed planet. At first believing themselves in the midst of World War I, they realise it to be one of many War Zones overseen by the War Lords, who have kidnapped large numbers of human soldiers to form the greatest army the universe has ever seen. At the helm of this plot is the War Chief, another renegade Time Lord like the Doctor. The creeping realisation sets in that the Doctor cannot solve this problem alone, and that his days of wandering may be at an end...

After a catastrophic global war, a young filmmaker awakens in the carnage and seeks refuge in the only other survivor: an eccentric, ideologically opposed figure of the United States military. Together, they brave the toxic landscape in search of safety... and answers.

The Doctor and Ruby Sunday have faced the Bogeyman, fought against Maestro, and survived the battlefield of Kastarion 3. In the epic two-part season finale, The Doctor and Ruby arrive at UNIT headquarters on a top-secret mission and a long-buried secret awaits…

When the Second Doctor, Polly, Ben and Jamie visit a human colony that appears to be one big holiday camp, they think they have come across a truly happy place. Yet a shadowy presence soon makes them realise that the surface contentment is carefully controlled.

The TARDIS arrives on Earth in July, 1966, on a runway at Gatwick Airport. Polly witnesses a murder in a nearby hangar and is then kidnapped by the perpetrator, Spencer of Chameleon Tours. Ben also vanishes. The Second Doctor and Jamie are left to convince the sceptical airport Commandant there has been foul play.

A man's attempts to construct the ultimate romantic weekend backfire when his quest for perfection traps his lover in an infinite loop.

During routine manoeuvres near Hawaii in 1980, the aircraft-carrier USS Nimitz is caught in a strange vortex-like storm, throwing the ship back in time to 1941—mere hours before the Japanese attack on Pearl Harbor.