Doctor WhoSeason 21

TV-PG
The Twin Dilemma, the first story with Colin Baker as the Sixth Doctor, aired last in the season. This season saw the departure of companions Tegan, Turlough and Kamelion and introduced Peri. Most episodes were the traditional twenty-five minute length. However, due to coverage of the 1984 Winter Olympics, Resurrection of the Daleks was re-edited before airing and shown as two forty-five minute episodes.

Where to Watch Doctor Who • Season 21

24 Episodes

  • Warriors of the Deep (1)
    E1
    Warriors of the Deep (1)Earth's ocean floor, 2084. With two superpowers poised on the brink of a devastating photonic war, a missile base comes under attack from the reptilian Sea Devils and Silurians, intent on eradicating the upstart human race and reclaiming the planet…
  • Warriors of the Deep (2)
    E2
    Warriors of the Deep (2)Just as the Doctor gains a tentative trust from the humans, a Silurian battle cruiser approaches. The Doctor warns Commander Vorsha to hold his fire and find out what they want, but is the level-headed commander one who'll listen?
  • Warriors of the Deep (3)
    E3
    Warriors of the Deep (3)With Silurians and Sea Devils attacking the air locks, the saboteurs use the distraction to launch plans for disabling vital functions of the base. With all the strife going on around him, and an electricity-generating myrka on the loose, the Doctor endeavors to bring a little sunshine into their unhappy undersea lives.
  • Warriors of the Deep (4)
    E4
    Warriors of the Deep (4)With Silurians in control of the base, Icthar reveals his plan for a final solution to Earth's human problem, which presents the Doctor a great moral dilemma.
  • The Awakening (1)
    E5
    The Awakening (1)A growing crack, a missing grandfather, a disfigured purse-snatcher, the image of an old man, and a dirty 15th century peasant boy add up to another life-threatening mystery for the Doctor to solve in a little village that's celebrating the anniversary of when the English Civil War hit town.
  • The Awakening (2)
    E6
    The Awakening (2)The Malus, an alien that's purely evil, needs the civil war re-enactments to become authentic so it can feed off the psychic energy of dying and embattled men and fully revive. Not if the Doctor can derail things, of course.
  • Frontios (1)
    E7
    Frontios (1)The planet Frontios, in the distant future. Following Earth's destruction, a tiny colony struggles to eke out a life on this desolate world. But where do the bombardments that threaten them originate from? Little does the Doctor suspect that somewhere nearby lurks a power capable of ripping even the TARDIS apart…
  • Frontios (2)
    E8
    Frontios (2)Following the destruction of the TARDIS, the only part of it left is the hat stand. So Turlough uses it as a weapon! Plantagenet gets swallowed by the earth, and Norna and Turlough discover the Tractators.
  • Frontios (3)
    E9
    Frontios (3)Trying to rescue the Doctor from the Tractator's trap, Tegan lands them both in even more trouble. Turlough goes a bit mad, and reckons he knows the evil of the Tractators from old.
  • Frontios (4)
    E10
    Frontios (4)The Doctor tries to deal with the Tractator's cunning plan, despite Turlough's best intervention. They discover the splintered TARDIS in the tunnels beneath the planet's surface, but how will they put it together again?
  • Resurrection of the Daleks (1)
    E11
    Resurrection of the Daleks (1)London's Docklands, 1984. Why are uniformed policemen gunning down strangely-dressed vagrants in broad daylight? A prison ship in the far future - who is the sole prisoner aboard the craft? And why are these two locations linked by the time corridor the TARDIS has been sucked into?
  • Resurrection of the Daleks (2)
    E12
    Resurrection of the Daleks (2)While Davros looks into solving a small problem offered up by the Movellans, the Daleks have not overlooked the Time Lords for all their years of interest and attention paid them, hoping to make of the Doctor and his companions emissaries of their appreciation, in order to thank them all to the fullest and permanently.
  • Planet of Fire (1)
    E13
    Planet of Fire (1)Lanzarote, 1985. Archaeologist Howard Foster raises a strange metal artefact from the sea floor. But how is it linked to the signal the TARDIS received? Why is Turlough suddenly so worried? And why is Kamelion acting so erratically?
  • Planet of Fire (2)
    E14
    Planet of Fire (2)While the Master, victim of his own attempt to improve his TCE weapon, seeks restoration through Sarn's numismaton gas, the truth of Turlough's past comes out at last, though to guarantee the safety of his brother and the Sarn people, Turlough must consider a great personal sacrifice.
  • Planet of Fire (3)
    E15
    Planet of Fire (3)Sarn prophesy foretells of an outsider who will come to aid the people. It's a role the Master is more than delighted to fill, which finally presents Timanov, the Sarn religious leader, the unbridled support he's sought in his campaign to cull the faithless from among his people. Turlough's secret past, however, is somehow intricately involved in all this, and the reluctance of its disclosure is enough to threaten all friendly ties with the Doctor.
  • Planet of Fire (4)
    E16
    Planet of Fire (4)While the Master, victim of his own attempt to improve his TCE weapon, seeks restoration through Sarn's numismaton gas, the truth of Turlough's past comes out at last, though to guarantee the safety of his brother and the Sarn people, Turlough must consider a great personal sacrifice.
  • The Caves of Androzani (1)
    E17
    The Caves of Androzani (1)The planet Androzani Minor, the distant future. In the planet's caves war rages between government troops and the android warriors of the mysterious Sharaz Jek. But what makes spectrox, the substance they battle to control, so valuable? And how far will the Doctor go to protect his companion?
  • The Caves of Androzani (2)
    E18
    The Caves of Androzani (2)Having been saved from execution by Sharez Jek and his androids, Jek takes a shine to Peri, and wants her with him forever. Salateen tells the Dr and Peri that they are dying from Spectrox toxemia, but there is an antidote.
  • The Caves of Androzani (3)
    E19
    The Caves of Androzani (3)The situation on Androzani Minor is building toward a violent confrontation, and the Doctor and Peri are slowly succumbing to spectrox toxemia.
  • The Caves of Androzani (4)
    E20
    The Caves of Androzani (4)Chellak and his men attack Jek's base. The Dr. crash-lands the ship, and must escape from his captors to find the antidote to the Spectrox poisoning and save Peri. He does so, but at a staggering cost.
  • The Twin Dilemma (1)
    E21
    The Twin Dilemma (1)Earth, the future. The genius Sylvest twins, child prodigies, are kidnapped by the mysterious Professor Edgeworth and taken to the planet Jaconda. But who is Edgeworth? Why does he serve the giant slug Mestor? And what is Mestor's plan?
  • The Twin Dilemma (2)
    E22
    The Twin Dilemma (2)The Doctor takes Peri to Titan 3, a desolate hunk of rock in space where he hopes to find some solitude for a while. Instead he finds the lone but unconscious survivor of a recent spaceship crash in sight of a mound-shaped complex where no formalised structure should exist.
  • The Twin Dilemma (3)
    E23
    The Twin Dilemma (3)The Doctor arrives on Jaconda, once lush and green, to find it completely devastated by giant gastropods. Old legends about the planet's half-human/half-slugs weren't just myths after all. With or without help from the Doctor and his unpredictable mood swings, Lt. Lang is up for rescuing the twins, who are finally informed of the grand purpose they've been brought to Jaconda to accomplish.
  • The Twin Dilemma (4)
    E24
    The Twin Dilemma (4)The Doctor and Edgeworth deduce that the real plan of Mestor, the gastropod ruler of Jaconda, will not only destroy Jaconda but lead to the devastation of other planets. Together they hope to thwart him despite his formidable ability at slipping into people's minds and controlling them.
  • Peter DavisonThe Doctor
  • Nicola BryantPerpugilliam "Peri" Brown
  • Janet FieldingTegan Jovanka
  • Mark StricksonVislor Turlough
  • John Nathan-TurnerProducer
  • Peter HowellTheme Song Performance
  • Ron GrainerMain Title Theme Composer
  • Eric SawardScript Editor

Doctor Who • Season 21 Ratings & Reviews

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