The season featured a story arc involving E-Space and the return of the Master who had stolen a new body rather than regenerate. The stories were darker and more adult in tone than those during the Graham Williams era. They also attempted to emphasise science, much to the satisfaction of both script editor Christopher H. Bidmead and executive producer Barry Letts. Notably, this season revolves around the theme of entropy, linking together all of its stories in a rare phenomenon for the show (while other story arcs would be linked together via people, objects, etc, the use of an overarching the
All episodes — Season 18
S18 E1The Leisure Hive (1)
Aug 30, 19806.524 min
The planet Argolis, around the year 2290. The Argolins live in a huge shielded city, protected from the irradiated wasteland outside. The planet's survival depends on the tourists their Leisure Hive attracts. But a series of horrific deaths
S18 E2The Leisure Hive (2)
Sep 6, 19806.221 min
Another man is found dead, strangled by the Doctor's scarf, so the Doctor is put on trial. By some of the archaic rules of law, he's made to "prove" his innocence by becoming a test subject in a new tachyon experiment with time. The result
S18 E3The Leisure Hive (3)
Sep 13, 19806.222 min
With the Doctor suffering from the time experiment, the clandestine schemes of others start coming to light, along with the secreted purposes to which the tachyonic generator has been used.
S18 E4The Leisure Hive (4)
Sep 20, 19806.622 min
With the saboteur and murderer revealed and arrested, peace should now be restored, but a new threat emerges - a war-monger who's both ready and eager to aggress upon other worlds with a newly manufactured warrior army.
S18 E5Meglos (1)
Sep 27, 1980625 min
The desert planet Zolpha-Thura, the 1980s. Giant intelligent megalomaniac cactus Meglos is planning to conquer the galaxy but first it needs the dodecahedron, a powerful energy source currently on the planet Tigella. To get it back Meglos r
S18 E6Meglos (2)
Oct 4, 19806.222 min
With the TARDIS occupants trapped in a chronic histeratic loop (forever reliving the same moment in time), the devious Meglos - disguised as the Doctor - gains the trust of the Tigellans along with full and private access to their power cha
S18 E7Meglos (3)
Oct 11, 19806.222 min
Can Romana escape the Gaztaks? What has become of the Dodecahedron? What pressing appointment awaits the Doctor?
S18 E8Meglos (4)
Oct 18, 19806.220 min
With the Doctor about to be ritualistically sacrificed to appease the god Ti for stealing the dodecahedron, Meglos and the pirates return to Zolfa-Thura with the dodecahedron to fire up an ancient weapon and blast Tigella out of existence.
S18 E9Full Circle (1)
Oct 25, 19806.725 min
Deep space, an unknown time - on course for Gallifrey, the TARDIS passes through a strange disruption. When they materialise, the scanner shows the Time Lord homeworld... but the travellers have passed into the negative pocket universe of E
S18 E10Full Circle (2)
Nov 1, 19806.623 min
As the humanoid community takes refuge in their crashed spaceship, venomous marsh spiders begin to hatch from the local fruit while bestial marshmen emerge from the waters to walk the land. It is quite apparent that the marshmen desire entr
S18 E11Full Circle (3)
Nov 8, 19806.422 min
Infection from a spider bite causes Romana's personality to change. Meanwhile the Doctor, after discovering that the spaceship society is in a perpetual state of repair and upgrade, has morality issues with the ship's leading scientist who
S18 E12Full Circle (4)
Nov 15, 19806.825 min
Marshmen invade the Terradonian ship thanks to Romana, who seems to be in communion with them. While the ship's inhabitants flee for their lives, the Doctor discovers a crucial fact why these humanoids can never return to the planet Terrado
S18 E13State of Decay (1)
Nov 22, 19807.123 min
Still trapped in negative E-Space, the TARDIS lands on an unnamed world to find a society sliding back into feudalism. What is the secret of the Three Who Rule? And what ancient enemy of the Time Lords is stirring again on this world...?
S18 E14State of Decay (2)
Nov 29, 1980724 min
The Doctor and Romana are escorted to the tower to meet the royal leaders, hoping they can find answers to why this society evolves backwards. The Doctor recognizes the tower as an old Earth spaceship, and further finds that the old fuel ta
S18 E15State of Decay (3)
Dec 6, 1980725 min
The Doctor finds archive material in the TARDIS that tells him he's dealing with an ancient enemy of the Time Lords, a nearly indestructible king vampire who's ready to revive and reenter normal space, spreading death, once again, across th
S18 E16State of Decay (4)
Dec 13, 1980725 min
The Doctor joins the villagers' revolt against their vampire rulers, unsure how to kill the king vampire. Meanwhile Adric is first in line to join the new vampire order while Romana is laid out as a sacrificial Time Lord for the awakening k
S18 E17Warriors' Gate (1)
Jan 3, 19816.323 min
The TARDIS is drawn into an empty white void, somewhere between universes. But they are not the only ones trapped there.
S18 E18Warriors' Gate (2)
Jan 10, 19816.624 min
When Rorvik learns that Romana is a time sensitive, he takes her prisoner, forcing her to find a way out of the void. The Doctor attempts to discover what lies beyond the mirror.
S18 E19Warriors' Gate (3)
Jan 17, 19816.623 min
While Biroc leads the Doctor to a view of the Tharil's lordly past, Romana learns more about the damaged freighter and the cold-heartedness of its crew. Meanwhile Commander Rorvik, confounded by the time mirror inside the universal center g
S18 E20Warriors' Gate (4)
Jan 24, 19816.625 min
The Doctor deduces that the freighter is a slave ship loaded up with Tharils to be sold as time machine components, but the immense weight of Rorvik's damaged ship, designed to contain the Tharils, is now collapsing the fragile void of the
S18 E21The Keeper of Traken (1)
Jan 31, 19817.425 min
The planet Traken. The Traken union is a society living in perfect harmony, watched over by the powerful but benign Keeper. But now the Keeper is dying, and he senses a great evil within his protectorate. Can the Doctor help him discover th
S18 E22The Keeper of Traken (2)
Feb 7, 19817.325 min
Tremas claims consular privilege to protect the Doctor and Adric from execution, though it binds his fate to theirs if they're found guilty of murder. Melkur strengthens his hold over Kassia while Seron decides to have rapport with The Keep
S18 E23The Keeper of Traken (3)
Feb 14, 19817.524 min
With Tremas falling under suspicion, due to his association with the Doctor, a new Keeper Nominate is named. Now, with everything in place, Melkur has only a short wait before his full malevolence can unfold.
S18 E24The Keeper of Traken (4)
Feb 21, 19817.526 min
With the merciless Melkur in control of The Source, the Doctor and his allies have only a slim chance of deposing him, which also puts the peace of the Traken Union in severe jeopardy.
S18 E25Logopolis (1)
Feb 28, 19817.625 min
Deciding to repair the TARDIS' chameleon circuit, the Doctor goes to Earth to find a real police box. But an old enemy is one step ahead of him.
S18 E26Logopolis (2)
Mar 7, 19817.525 min
The Doctor, aware that his time may soon be ending, travels to the Logopolis where a series of fateful events are set in motion.
S18 E27Logopolis (3)
Mar 14, 19817.525 min
With Nyssa from Traken unexpectedly rejoining the group, Adric aids the Monitor of Logopolis in trying to save the Doctor before time runs out. The Master, at liberty to prepare, is finally ready to reveal his true target, which unknowingly
S18 E28Logopolis (4)
Mar 21, 19818.326 min
With the universe collapsing, the Doctor forms an uneasy alliance with the Master to save it. In case all does not go well, the Watcher takes the Doctor's companions to a safe place, but his plans for them don't stop there. The one hope for