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.
All episodes — Season 21
S21 E1Warriors of the Deep (1)
Jan 5, 19845.125 min
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 th
S21 E2Warriors of the Deep (2)
Jan 6, 19845.325 min
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?
S21 E3Warriors of the Deep (3)
Jan 12, 19845.525 min
As Vorshak's crew are cut down by Sauvix's Sea Devil Warriors, the Doctor is running out of ways to broker a peace between the opposing species.
S21 E4Warriors of the Deep (4)
Jan 13, 19845.325 min
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.
S21 E5The Awakening (1)
Jan 19, 19846.526 min
The sleepy English village of Little Hodcombe, 1984. The village re-enactment of the English Civil War is in full swing, but a malign alien presence intends the mock-battles to be rather more realistic than planned...
S21 E6The Awakening (2)
Jan 20, 19845.825 min
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.
S21 E7Frontios (1)
Jan 26, 19846.825 min
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 tha
S21 E8Frontios (2)
Jan 27, 19847.125 min
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.
S21 E9Frontios (3)
Feb 2, 19847.125 min
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.
S21 E10Frontios (4)
Feb 3, 19847.125 min
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?
S21 E11Resurrection of the Daleks (1)
Feb 8, 19848.446 min
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
S21 E12Resurrection of the Daleks (2)
Feb 15, 1984846 min
As the surviving station crew work to destroy the space station, Davros consolidates his power and the Daleks launch a fiendish scheme to use the Doctor against the Time Lords.
S21 E13Planet of Fire (1)
Feb 23, 19846.625 min
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?
S21 E14Planet of Fire (2)
Feb 24, 19846.825 min
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, Turlo
S21 E15Planet of Fire (3)
Mar 1, 19846.724 min
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 c
S21 E16Planet of Fire (4)
Mar 2, 19846.525 min
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, Turlo
S21 E17The Caves of Androzani (1)
Mar 8, 19848.525 min
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
S21 E18The Caves of Androzani (2)
Mar 9, 19848.626 min
The Doctor and Peri have been rescued from the firing squad by the mysterious Sharaz Jek. But he has his own plans for them. And why are they suddenly feeling ill?
S21 E19The Caves of Androzani (3)
Mar 15, 19848.625 min
The situation on Androzani Minor is building toward a violent confrontation, and the Doctor and Peri are slowly succumbing to spectrox toxemia.
S21 E20The Caves of Androzani (4)
Mar 16, 19848.826 min
Events on Androzani reach a bloody climax. Will the Doctor and Peri survive the carnage? And at what cost?
S21 E21The Twin Dilemma (1)
Mar 22, 19845.225 min
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?
S21 E22The Twin Dilemma (2)
Mar 23, 19846.126 min
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
S21 E23The Twin Dilemma (3)
Mar 29, 19845.625 min
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 unpred
S21 E24The Twin Dilemma (4)
Mar 30, 19845.526 min
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 sli