The Doctor and Sarah arrive in Renaissance Italy unaware that they have brought a deadly alien energy force with them.

The Mandragora energy joins forces with the secret Brotherhood of Demnos. Count Federico plots to steal the Dukedom of San Martino from his nephew, Giuliano.

Tempted by the promises of ultimate power offered by Mandragora, Hieronymous plots to eliminate the threat posed by the Doctor and uses an unwitting Sarah as his weapon.

As the leading scholars of the era assemble in the palace for the masque, Mandragora prepares to attack, intent on sending the world into a new dark age.

England, the near future. The TARDIS materialises in a quarry and Sarah is trapped under a rockfall. But what is the origin of the fossilised hand she is found gripping ? And who is the Eldrad she keeps mumbling about ?

The energy of the reactor has returned the mysterious Eldrad to life. The Doctor agrees to take her back to Kastria. But what is waiting for them there?

The Doctor and Sarah race to save the mortally wounded Eldrad. But they find that everything is not quite as she told them.

Gallifrey, planet of the Time Lords. Summoned home by a premonition of murder, the Doctor discovers a dark conspiracy at the highest levels of Time Lord society... and his oldest enemy, who poses a threat to the existence of Gallifrey itself...

The President of the High Council has been killed and the Doctor is the prime suspect. The Time Lords are eager to dispense quick justice and the Doctor must race agains the clock to discover the truth... and an old enemy.

The Doctor has entered the computation Matrix to prove his innocence. But his opponent is prepared for him and the two engage in a mental duel to the death.

The Doctor has won his fight in the Matrix and revealed the assassin. But the Master is not defeated and sets a plan in motion that could destroy the Time Lords.

An unnamed planet, the distant future. Arriving in a place that seems oddly familiar, the Doctor finds the savage Sevateem tribe battling to free their captive god, Xoanon, from the Evil One and his Tesh servants. But can the whole situation really be the Doctor's fault?

The Sevateem launch another attack to try to free Xoanon as the Doctor tries to figure out his role in their past. But his only chance to win their trust is to face a deadly test.

The Doctor has broken through the barrier and found the Tesh. But he comes to an awful realisation about Xoanon.

The Doctor tries to fix the mad computer Xoanon. But it is determined to stop him – even if it must destroy the entire world!

An unnamed world, an unknown time. A vast mining vessel trawls a sea of mineral sand for valuable ores, the tiny human crew served by an army of humanoid robots. But as the Doctor and Leela arrive, one of the crew is found murdered... and if they didn't do it, who did?

The Doctor and Leela are suspected of murder. But the real foe is using robots to cut down the crew – and even sabotage the sand miner itself!

One of the crew is the insane Taren Capel, who is using robots to carry out the murders. The Doctor discovers that there are also others who aren't what they appear to be either.

The Doctor and the surviving humans fight for their lives against Taren Capel and his growing army of deadly robots.

London, the 1890s. As magician Li H'Sen Chang captivates audiences, a spate of disappearances amongst young women goes largely unnoticed. But almost upon their arrival, the Doctor and Leela find themselves confronting the feared Tong of the Black Scorpion, and a menace from another time. And there's something fishy in the sewers, too...

The Doctor and Leela investigate the strange events in Victorian London. But a mysterious masked figure lurks in the shadows.

As Li H'Sen Chang works to secure the time cabinet, Leela pursues and investigates his master – the mysterious and murderous Weng-Chiang.

The Doctor and Leela attend Li H'Sen Chang's performance, hoping to confront the magician. But his master Weng-Chiang has other plans…

The Doctor and his allies try to track down Weng-Chiang before he can activate the time cabinet and possibly destroy London.

The Doctor and Weng-Chiang have their final confrontation in the mysterious House of the Dragon -- watched by the evil duplicitous Mr. Sin.