England, the late 1970s. The Doctor and Romana arrive in search of the third segment. But the Tracer readings are erratic and something ominous is happening with an ancient stone circle...

The quest for the Third Segment has landed the Doctor and Romana in the midst of a druidic cult centred on a stone circle. But the stones are not what they seem, and somewhere out there is a blood-thirsty Celtic goddess.

Chased by blood-thirsty stones, the Doctor must find a way to rescue Romana. What awaits him in the theoretical absurdity of hyperspace?

Facing a sentence of death from merciless justice machines, the Doctor must play for time while Romana tries to discover just who Vivian Fey really is.

Arriving on Tara, Romana locates the fourth segment of the Key to Time with ease. But getting it away proves more difficult, as she is captured by the scheming Count Grendel who wants the throne of Tara for himself.

The Doctor must employ a desperate gambit to keep the evil Grendel off the throne. And the Count has a new pawn to play - Romana.

The battle for control of Tara turns into a duel of wits between the Doctor and Grendel. But the Count shows he has more treacherous tricks up his sleeve.

Grendel plans two weddings and a funeral to cement his hold over Tara. The Doctor and K-9 race to foil him and save the Time Lady's life.

Paris, 1979. The Doctor and Romana are here on holiday, but something is disturbing the flow of time. Could the time travel experiments of Count Scarlioni be to blame?

Captured by the Count, the Doctor and Romana uncover an elaborate plan to steal the Mona Lisa. But there is more to Scarlioni's plans than a simple theft.

The Doctor and Romana unwrap an intricate plot involving aliens, time travel and the Mona Lisa. How is Count Scarlioni living in two times at once? And what does he want?

Scaroth is determined to go back 400 million years in time to prevent a mistake. But the Doctor must stop him – because the consequences would be disastrous.

The planet Chloris. Drawn here by a mysterious distress signal, the Doctor becomes the prisoner of the ruthless Adrasta. A strange and deadly pit awaits those who displease her.

The Doctor is in a pit with a deadly creature. And Adrasta has plans for Romana and K-9.

The Doctor has come face to face with a massive green creature. Adrasta goes into the mines to kill the monster. But everything is not as it appears…

The truth about the creature is revealed. But its imprisonment may have already set in motion a terrible revenge.

The planet Argolis, around the year 2290. The Argolins live in a huge shielded city, protected from the irradiated wasteland outside. The planet's survival depends on the tourists their Leisure Hive attracts. But a series of horrific deaths seems to jeopardise that future - can the Doctor and Romana find a solution?

Another man is found dead, strangled by the Doctor's scarf, so the Doctor is put on trial. By some of the archaic rules of law, he's made to "prove" his innocence by becoming a test subject in a new tachyon experiment with time. The result will prove his innocence or guilt, so they say.

With the Doctor suffering from the time experiment, the clandestine schemes of others start coming to light, along with the secreted purposes to which the tachyonic generator has been used.

With the saboteur and murderer revealed and arrested, peace should now be restored, but a new threat emerges - a war-monger who's both ready and eager to aggress upon other worlds with a newly manufactured warrior army.