Beloved companion Sarah Jane Smith, played by Elisabeth Sladen, makes her first appearance and so do the Sontarans in the form of Linx, trapped on medieval Earth and abducting scientists from the future to aid his escape.
UNIT investigates when scientists go missing kidnapped by an alien trapped in the 13th Century. Travelling back in time in the TARDIS, the Doctor is unaware that he has stowaway.
UNIT investigates when scientists go missing kidnapped by an alien trapped in the 13th Century. Travelling back in time in the TARDIS, the Doctor is unaware that he has stowaway.
The Doctor discovers that the alien is a Sontaran warrior called Linx who is trying to repair his spaceship. Sarah is convinced that the Doctor is responsible for the abductions.
The Doctor discovers that the alien is a Sontaran warrior called Linx who is trying to repair his spaceship. Sarah is convinced that the Doctor is responsible for the abductions.
Linx is providing advanced weaponry to Irongron and his men who prepare to attack Sir Edward's castle. The Doctor is forced to improvise a defence, but will it be enough?
Linx is providing advanced weaponry to Irongron and his men who prepare to attack Sir Edward's castle. The Doctor is forced to improvise a defence, but will it be enough?
As the repairs to Linx's spaceship are completed and he prepares to take off, the Doctor races to save the captured scientists and to prevent the course of history being changed.
As the repairs to Linx's spaceship are completed and he prepares to take off, the Doctor races to save the captured scientists and to prevent the course of history being changed.
The Doctor plans to capture a dinosaur so that he can discover who is transporting them through time. But Mike Yates is in league with the enemy and is ordered to stop the Doctor.
The Doctor plans to capture a dinosaur so that he can discover who is transporting them through time. But Mike Yates is in league with the enemy and is ordered to stop the Doctor.
The Doctor has captured a Tyrannosaurus Rex but the conspirators don't intend for it to remain captive for long. Sarah follows a lead but places herself in the hands of the enemy.
The Doctor has captured a Tyrannosaurus Rex but the conspirators don't intend for it to remain captive for long. Sarah follows a lead but places herself in the hands of the enemy.
Sarah awakens to discover that she is on a spaceship that left Earth months ago and is heading for a new world. The Doctor is framed for causing the return of the dinosaurs.
Sarah awakens to discover that she is on a spaceship that left Earth months ago and is heading for a new world. The Doctor is framed for causing the return of the dinosaurs.
The TARDIS suffers a power drain and is forced down on the planet Exxilon. Sarah is captured by the primitive inhabitants and the Doctor comes face to face with his oldest enemies.
The TARDIS suffers a power drain and is forced down on the planet Exxilon. Sarah is captured by the primitive inhabitants and the Doctor comes face to face with his oldest enemies.
The Daleks weaponry is rendered useless by the power drain and they are forced to make a truce with the Doctor and the members of the expedition from Earth.
The Daleks weaponry is rendered useless by the power drain and they are forced to make a truce with the Doctor and the members of the expedition from Earth.
The Doctor and Bellal arrive at the centre of the Exxilon city but the Daleks are preparing to depart and launch a deadly plague missile that will kill everyone left behind.
The Doctor and Bellal arrive at the centre of the Exxilon city but the Daleks are preparing to depart and launch a deadly plague missile that will kill everyone left behind.
The Daleks force the Exillons to work as slave labour to mine the life saving parrinium. The Doctor and Bellal brave the puzzles and traps of the Exxilon city.
The Daleks force the Exillons to work as slave labour to mine the life saving parrinium. The Doctor and Bellal brave the puzzles and traps of the Exxilon city.
The Doctor makes a return visit to Peladon some years after his previous visit. There he discovers that several miners have died and the ghost of Aggedor is to blame.
The Doctor makes a return visit to Peladon some years after his previous visit. There he discovers that several miners have died and the ghost of Aggedor is to blame.
Desperate to avoid a revolt from the miners, the Doctor attempts to expose the fraud of Aggedor's ghost. Alpha Centauri has summoned Federation troops, but whose side are they on?
Desperate to avoid a revolt from the miners, the Doctor attempts to expose the fraud of Aggedor's ghost. Alpha Centauri has summoned Federation troops, but whose side are they on?
Commander Azaxyr and his Ice Warriors are revealed as traitors, in league with Galaxy 5. The Doctor intends to turn Aggedor against Azaxyr, but it may already be too late.
Commander Azaxyr and his Ice Warriors are revealed as traitors, in league with Galaxy 5. The Doctor intends to turn Aggedor against Azaxyr, but it may already be too late.
The Doctor and the miners take the upper hand in the fight to reclaim Peladon from the Ice Warriors. But Eckersley is unwilling to give up and takes Queen Thalira hostage.
The Doctor and the miners take the upper hand in the fight to reclaim Peladon from the Ice Warriors. But Eckersley is unwilling to give up and takes Queen Thalira hostage.
The Doctor receives a mysterious package from his old companion, Jo Grant. Sarah joins Mike Yates to investigate sinister events at a Buddhist meditation centre.
The Doctor receives a mysterious package from his old companion, Jo Grant. Sarah joins Mike Yates to investigate sinister events at a Buddhist meditation centre.
Lupton, now under the control of a giant spider, infiltrates UNIT HQ and steals the Metebelis crystal. But the Doctor is unwilling to give it up so easily and a chase begins.
Lupton, now under the control of a giant spider, infiltrates UNIT HQ and steals the Metebelis crystal. But the Doctor is unwilling to give it up so easily and a chase begins.
Following Lupton, Sarah is transported to Metebelis 3 where she is captured by the human villagers. The Doctor uses the TARDIS to follow Sarah, but the spiders are waiting.
Following Lupton, Sarah is transported to Metebelis 3 where she is captured by the human villagers. The Doctor uses the TARDIS to follow Sarah, but the spiders are waiting.
With the Doctor in a coma, his only hope of survival lies with a device inside the TARDIS. Sarah is captured by the spiders and is held prisoner in their larder.
With the Doctor in a coma, his only hope of survival lies with a device inside the TARDIS. Sarah is captured by the spiders and is held prisoner in their larder.
Beloved companion Sarah Jane Smith, played by Elisabeth Sladen, makes her first appearance and so do the Sontarans in the form of Linx, trapped on medieval Earth and abducting scientists from the future to aid his escape.