England, the 12th century. Robber baron Irongron is recruited by Linx, a Sontaran warrior whose starship has been forced down on Earth. Linx is forced to use a time-travel device to steal resources and scientists from the future to repair his ship, but in doing so involves UNIT and the Doctor...

The Doctor tracks the missing scientists to Irongron's castle, where Linx is using them to repair his spaceship and construct advanced weapons for Irongron.

The Doctor escapes the castle with Sarah and Hal and must persuade Sir Edward to trust him before Irongron launches an attack on them.

The Doctor attempts to return the scientists to their own time, before Linx tries to use his spaceship and destroys the entire castle.

The Doctor and Sarah return to London in the present day only to find the city strangely deserted, while nearby UNIT are dealing with a series of monster appearances.

The Doctor attempts to solve the mystery of the monster invasion. His first move - the capture of a dinosaur.

Yates sabotages the Doctor's equipment to stop him finding the location of Whitaker's base but then the tyrannosaur escapes, placing Sarah in danger.

Sarah attempts to find a way off the spaceship while the Doctor tries to track down the source of the time displacements.

The Doctor has been framed as the monster maker by Finch and is on the run from the army, while Sarah attempts to alert UNIT to what Grover is up to.

The Doctor is rescued from Finch by the Brigadier and Benton and tries to persuade them to stop Grover before millions of people are erased from history.

The barren planet Exxilon, some time in the future. The TARDIS is forced down by a total power failure and the Doctor and Sarah meet a stranded Earth crew who came here to mine for priceless medical supplies. But what is causing the power failures? And why have the Daleks come here too?

The Doctor and the MSC crew join forces with the Daleks to mine the parrinium, only to come under attack from the Exxilons.

The Doctor and Sarah meet up with Bellal, who helps them escape from the Daleks and explains the origin of the City.

The Doctor and Bellal continue to penetrate the City's defences while Sarah and Jill try to stop the Daleks leaving with the parrinium.

The planet Peladon, some time in the future. Mining disputes threaten the peace of the planet, and as the Doctor and Jo arrive, it seems that the ghost of Aggedor walks once more...

The Doctor is rescued by Gebek, prompting him to try and help the miners, but his advice results in Ettis launching another attack on the armoury.

The Doctor and Sarah pacify Aggedor and the Doctor encourages the Queen to make peace with the miners, but Ortron soon has him under arrest again.

The Ice Warriors take control of the planet and force the miners to return to work but Ettis takes the opportunity to try and destroy the citadel.

Sarah and Alpha Centauri decide to try and alert the Federation to what the Ice Warriors are up to but first they have to escape from the throne room.

The Doctor turns the Aggedor spirit against the Ice Warriors to aid the Peladonians in their battle but Eckersley attacks him with the security system.

While the Doctor carries out an investigation into ESP, Mike Yates asks Sarah to look into some strange goings on at a meditation centre he's attending.

Lupton forms an alliance with the spider to steal the Doctor's blue crystal, while Sarah and Mike attempt to alert people to what they've seen.

The Doctor and Sarah head to the meditation centre to try and get the crystal back while Lupton prepares to return it to Metebelis Three. But all their plans are disrupted when it is stolen by Tommy.

Sarah is captured by the spiders' guards while the Doctor tries to help Arak and the others strike back against the spiders.

The Doctor escapes from the spiders' larder only to encounter the Great One, while Sarah makes a deal with the Queen Spider.

K'Anpo persuades the Doctor he must face his fear and return the crystal to the Great One.But first they need to get past Barnes and his men.

Can the Doctor, now in his fourth incarnation, recover from his post regenerative trauma to save the Earth from Think Tank and their plot for world domination ?

The Doctor and Sarah Jane become convinced Think Tank are behind the electronic component thefts but are unable to stop them carrying out another raid.

Sarah Jane and Kettlewell infiltrate an SRS meeting to try and find out what Miss Winters is up to but there is a surprise in store.

UNIT attempt to get into the bunker to stop Miss Winters setting off the world's nuclear missiles but first they have to get past the K1.

The Doctor's attempt to give Harry a trip in the TARDIS sees the two of them and Sarah Jane arriving onboard a space station in the far future, with some rather deadly security mechanisms.

The Doctor and Harry revive the Ark's medtech, Vira, to help Sarah Jane. But when station commander Noah is revived, he becomes suspicious of the newcomers.

Knowing that Noah has been infected by the Wirrn, the Doctor persuades Vira to halt the reviving of her people, knowing it will place them in danger as well.

The Doctor tries to protect the humans still in cryogenic suspension from the Wirrn, who are determined to use Earth as their new breeding ground.

The Doctor, Sarah Jane and Harry teleport to Earth to ensure the planet is safe for the survivors on board Nerva Beacon to return and reinhabit their world. A Sontaran named Styre has captured a group of humans and is conducting experiments on them to discover the human body's weaknesses, as part of the Sontaran's goal for domination of the galaxy.

The Doctor learns that Styre has been experimenting on the Galsec crewmembers to pave the way for a Sontaran invasion of Earth and decides the only way to halt his plans is to challenge him to a duel.

The planet Skaro, the distant past. The Time Lords divert the Doctor, Sarah Jane and Harry to this war-torn world, and give the Doctor a mission: the evil of the Daleks is about to be born here, and the Doctor is to try to ensure they evolve into less lethally aggressive beings - or, failing that, to avert their creation altogether. But has even the Doctor the right to commit genocide?

The Doctor and Harry are taken to the Kaled bunker where Davros is preparing to demonstrate the Daleks, while Sarah Jane is captured by the Thals and taken to their city as a slave worker.

The Doctor and Harry head to the Kaled city to alert the authorities to Davros' plans while Sarah Jane and Sevrin are forced to work on the completion of the Thals' rocket.

The Doctor fails to prevent the Thals from destroying the Kaled city but they don't have long to enjoy their victory before the Daleks attack.

The Doctor is forced to give Davros full details of future Dalek victories but opposition to Davros' plans is growing among the Kaleds and soon there is open rebellion.

Gharman tries to convince the Kaleds to vote against the Dalek project but Davros has a trick up his sleeve, while the Doctor works to destroy the tape recording of Dalek victory and the Thals plan an intervention of their own.

The orbit of Jupiter, the 25th century. Arriving back on the Nerva Beacon much earlier in history, the Doctor and his friends discover the satellite beset by space plague while its crew struggles to keep space traffic away from Voga, the newest moon of Jupiter. But what is the connection between Voga, the plague, and some old enemies of the Doctor?

The Doctor transmits Sarah Jane and Harry down to Voga to cure Sarah Jane of the Cybermat's poison but Kellman's sabotage means he is unable to bring them back.

The Cybermen force the Doctor, Stevenson and Lester to carry bombs to the centre of Voga while Sarah Jane, Harry and Tyrum decide to contact Vorus.

The Doctor, Harry and Lester try to destroy the Cybermen's relay device, while the Vogans prepare to destroy Nerva even though Sarah Jane is still on board.

Scotland, the near future. Something is smashing oil rigs off the Scottish coast, and UNIT have been called in to investigate. The Brigadier summons the Doctor to Earth to help in the investigation, but it soon becomes clear some kind of alien presence is at work...

The Zygon traps the Doctor and Sarah Jane in a decompression chamber while Harry is taken to the aliens' underwater ship.

The Doctor and the Brigadier begin to realise who the Zygon imposters among them are while Sarah Jane discovers a secret tunnel to the underwater ship.

UNIT attempt to track down the Zygon ship while Broton prepares to have the Skarasen attack London.

The Doctor and Sarah answer a distress call and find themselves on Zeta Minor, the last planet of the known universe, where a Morestran expedition has gone missing.

The Doctor realises that Zeta Minor lies on the boundary between the universes of matter and anti-matter and something on the planet won't let the Morestrans leave.

The Doctor makes a deal with the Anti-Matter Beast to return all the anti-matter to the planet but Sorenson is determined to continue his research.

The Doctor tries to convince Sorenson to sacrifice himself for the rest of the crew but Salamar's attempt to deal with the situation causes their problems to multiply.

The Doctor and Sarah are drawn off course and, instead of UNIT HQ, they arrive on the same site in 1911.

The Doctor, Sarah and Laurence try to find a way to sever Sutekh's link to the mummies while poacher Ernie Clements finds the priory surrounded by a forcefield.

The Doctor and Sarah try to destroy Sutekh's rocket but the Osiran's mental powers prove too great for them.

Sutekh forces the Doctor to transport Scarman and a mummy to Mars, where the Doctor and Sarah try to stop them destroying the Eye of Horus.

The Doctor and Sarah return to Earth in the present day to find a strangely deserted village and woods stalked by white-clad figures.

The Doctor suspects Crayford brought something to Earth in his rocket, as he and Sarah find themselves hunted by UNIT.

The Doctor is captured by Styggron and left to die in the destruction of the fake village but Sarah escapes from the disorientation chamber to try and rescue him.

The Doctor and Sarah reach Earth and try to warn the research centre about the Kraal invasion before Styggron unleashes his virus.

The storm-lashed planet Karn. Near a graveyard of crashed starships, the demented surgeon Solon hides in his castle, the last acolyte of the Time Lord despot Morbius. He only needs one final item to make his master live again... and then the Doctor and Sarah arrive...

The Doctor is captured by the Sisterhood, and Sarah Jane is blinded freeing him. The Doctor has no choice but to go back for a cure, unaware that he is leaving Sarah Jane in the hands of a treacherous Dr. Solon and the renegade Time Lord Morbius.

While the Doctor goes to confront the Sisterhood to seek a cure for Sarah Jane's blindness, Solon realizes that he must transfer Morbius' brain into a new body before it is too late.

Morbius lives once more, but as a rampaging beast. The Doctor is forced to ally with Dr. Solon to bring him to heel, but the two disagree about what should happen to Morbius.

The Antarctic, the near future. A strange seed-pod is unearthed from 20-thousand-year-old ice. The Doctor and Sarah go to investigate, but are too late to prevent the pod infecting a scientist and unleashing a threat to all animal life on Earth...

Two employees of the millionaire Harrison Chase arrive at the Antarctic base, and they will stop at nothing to get hold of the second seed-pod.

The Doctor and Sarah Jane return to England after their Antarctic ordeal and Chase tries to eliminate them, but they escape and track him down at his estate, where he is preparing to open the Krynoid pod.

The Doctor is captured by Chase, who plans to breed the stolen Krynoid pod. He is placed in an automated compost hopper and only Sarah Jane can save him... but will she make it before the Krynoid grows to fruition ?

The Krynoid grows to a monstrous size and traps the Doctor and the others in a cottage. The creature demands they turn over the Doctor, while Chase seeks to make an alliance with the alien vegetation.

The Doctor, Sarah Jane, and Scorby are trapped in the manor as a possessed Chase stalks them from within, while the gigantic Krynoid prepares to crush them from without. Worse, the alien plant is ready to germinate, spreading its seeds across England.

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 Doctor and Professor Watson struggle to stop first Sarah Jane and then Driscoll from obeying the strange and dangerous orders of the stone hand, which has suddenly come to life.

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.