Season 20 - Episode Guide

On Gallifrey, someone commits a treasonous act and transmits the Doctor's bio-extract from The Matrix to a unknown being. Meanwhile on Earth, two students spend the night in a underground crypt in Amsterdam and are attacked by a alien creature.

With a anti-matter being trying to enter the universe through the Doctor, the Gallifreyan high council see's only one clear course of action. They decided to put the Doctor to death in order to prevent the occurrence.

The Council follows through with their death order and Omega holds the Doctor in Limbo. Commander Maxil discover's that Nyssa was right and the Doctors Bio-Extract had been transmitted from The Matrix.Tegan finds her cousin who is under alien control.

The Doctor having returned to Earth, finds Omega's Tardis and is not able to prevent Omega's transfer upon arrival. Omega being of anti-matter and unstable is on the verge of destroying the planet in his attempt to regain a body.

The Tardis lands on the home world of the Sumaran civilization. The Doctor did not set the co-ordinates for the landing and discovers that Tegan did. He starts questioning if the Mara is still active inside of her from their previous adventure on the Kinda world.

The Doctor finds out about the legend of the Mara's return. Tegan goes into the cave and see's a Mara skull in one of the mirrors. Tegan summons Lon to her.

Possessed Tegan and Lon try to find the location of the Great Crystal. The Doctor finds himself in prison with only Nyssa to get him out while Chela tells the Doctor about Dojjen and gives him Dojjen's journal.

The Mara's plan is close to fruition, the Doctor comes to prevent the Mara from finalizing the plan with the knowledge that Dojjen imparted to him.

The Black Guardian strikes a deal with a school student named Turlough to kill the Doctor. He promises him that he will take him back to his home planet if he does the job. Meanwhile The Doctor's Tardis is trapped by a hidden device near Turlough's school.

The Doctor is stranded on Earth in 1983 while Tegan and Nyssa are looking for him in 1977. Tegan and Nyssa encounter a injured man they believe to be the doctor. Both the Doctor And Tegan and Nyssa encounter Brigadier Lethbridge Stewart who seems to have no memory of The Doctor.

The Doctor travels to the orbiting spaceship with the Brigadier. Soon to discover a piece of Timelord technology on board the ship. Tegan and Turlough travel to the ship with their version of the Brigadier.

The Doctor is on the ship and his future looks bleak as he is about to loose all his Timelord abilities to the Mawdryn. Both the Brigadier's come in to the Mawdryns room with the Timelord artifact right as the transfer is starting.

Turlough sabotages the Tardis under the Black Guardian's direction and the Tardis materializes in the nearest ship. Nyssa is trapped in her room and has to escape into the spaceship the Tardis's emergency circuits have landed it on.

The two people the Doctor meets who have broken into the ship realize that they are on Terminus, where people who have the Lazar disease are sent to die. The Doctor finds it strange that the ship is at the exact center of the universe.

The guards think the Doctor and those with him are investigators since they are not Lazars and are armed. Nyssa is taken off to be treated for the disease by the Garm.

The Doctor discovers that the pilot had dumped the ships fuel billions of years ago and that the ship is going into another automatic fuel dump sequence because of the damaged engine. He determines that if the fuel gets dumped into space again, it will cause the destruction of the universe. Nyssa makes a decision that affects everyone.

The Doctor receives a warning from the White Guardian and is given co-ordinates to materialize the Tardis at. He lands the Tardis on a ship Captained by one of the Eternals. A Clairvoyant race that never dies and plays games involving mortals to relieve their boredom.

Captain Striker reveals to the Doctor that they are Eternal's and that they use ephemeral beings. The Black Guardian gets harsher with Turlough. The Captain takes the Tardis away from the Doctor.

Captain Wrack rescues Turlough and see's his coming aboard as a opportunity to invite all the other Captains over and use their visit to her advantage.

Captain Wrack sets Tegan up to destroy Striker and his ship without her knowing it. Tegan convinces Captain Wrack to send the Doctor back to Striker's ship where the Doctor works to foil her plot and defeat the Black Guardian.

The Doctor lands the Tardis in 1215 England at the Castle of Ranulf Fitzwilliam in the middle of a jousting tournament and the Doctor is immediately hailed as a demon by the king. The Doctor finds this very suspicious. SPOILER ALERT: If you are watching this episode for the first time, wait until it is over to view the main cast as that will give some of the plot away.

The Doctor having discovered that The Master is behind the false King, works to stop the Master from preventing the Magna Carta to be signed.

The Doctor finds his past selves being ripped away one by one. His past selves end on on his home planet, the world of Gallifrey. They discover that they are being transported to a place on Gallifrey called the Death Zone where Time Lords in a time long before Rassilon used to scoop up aliens from all over space and time to play deadly games with them. This was put to a end by the rise of Rassilon as the greatest of all the Time Lords. The 5 Doctors have to discover who is behind the plot.