Doctor Who — Season 20

All 22 episodes in airing order, with first-run dates and viewer ratings.

1. 01

   January 4, 1983 · 25m

   Arc of Infinity, Part One8.9

   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.

2. 02

   January 5, 1983 · 25m

   Arc of Infinity, Part Two8.9

   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.

3. 03

   January 11, 1983 · 25m

   Arc of Infinity, Part Three8.9

   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.

4. 04

   January 12, 1983 · 25m

   Arc of Infinity, Part Four8.9

   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.

5. 05

   January 18, 1983 · 25m

   Snakedance, Part One8.3

   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.

6. 06

   January 19, 1983 · 25m

   Snakedance, Part Two8.3

   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.

7. 07

   January 25, 1983 · 25m

   Snakedance, Part Three8.3

   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.

8. 08

   January 26, 1983 · 25m

   Snakedance, Part Four8.4

   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.

9. 09

   February 1, 1983 · 25m

   Mawdryn Undead, Part One9.1

   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.

10. 10

    February 2, 1983 · 25m

    Mawdryn Undead, Part Two9.3

    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.

11. 11

    February 8, 1983 · 25m

    Mawdryn Undead, Part Three9.1

    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.

12. 12

    February 9, 1983 · 25m

    Mawdryn Undead, Part Four9.3

    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 Brigadiers come in to the Mawdryns room with the Timelord artifact right as the transfer is starting.

13. 13

    February 15, 1983 · 25m

    Terminus, Part One9.3

    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.

14. 14

    February 16, 1983 · 25m

    Terminus, Part Two9.2

    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.

15. 15

    February 22, 1983 · 25m

    Terminus, Part Three9.3

    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.

16. 16

    February 23, 1983 · 25m

    Terminus, Part Four9.3

    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.

17. 17

    March 1, 1983 · 25m

    Enlightenment, Part One9.3

    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.

18. 18

    March 2, 1983 · 25m

    Enlightenment, Part Two9.3

    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.

19. 19

    March 8, 1983 · 25m

    Enlightenment, Part Three9.3

    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.

20. 20

    March 9, 1983 · 25m

    Enlightenment, Part Four9.3

    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.

21. 21

    March 15, 1983 · 25m

    The King's Demons, Part One9.5

    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.

22. 22

    March 16, 1983 · 25m

    The King's Demons, Part Two9.2

    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.