Plot
The Master, posing as a professor, gains access to a physical science research unit in the village of Wootton, near Cambridge. He conducts time experiments focused around transmitting matter by breaking it down into light waves. He is particularly interested in examining a trident-shaped crystal in his possession, using it to attract a being he addresses as Kronos.
The Third Doctor and Jo Grant visit the institute, following his hunch that the Master is back on Earth with his TARDIS. The experiments disrupt the normal flow of time and in one instance, Hyde, a researcher, is caught in the field of the experiment, and ages to more than eighty years. Brigadier Lethbridge-Stewart has the project evacuated and begins a hunt for the Master. The Doctor explains that Kronos is a "chronovore", a creature from outside time that feeds on it, attracted from the vortex to ancient Atlantis using a crystal trident larger than one seen to have been used by the Master. The Doctor suspects capturing the chronovore is the Master’s purpose, and that this represents a danger to the entire universe.
Meanwhile, the Atlantean High Priest of Poseidon, Krasis, is transported through interstitial time by the Master and brought to an office at the institute. The Master seizes the Seal of Kronos from the priest and uses it to conjure Kronos, a white, bird-like figure, who devours the Institute's Director, Dr Percival. Kronos is briefly contained by the Master, but breaks free, Krasis surmising the Master only has the smaller fragment of the original crystal.
The Doctor and his allies, alerted by the Master's actions, build a time flow analogue to interrupt the experiments. The Time Lords then duel using time as a weapon, leading to a series of bizarre temporal effects. When they pit their TARDISes against one another, the Doctor is ejected into the vortex, but survives thanks to Jo and his TARDIS.
In ancient Atlantis, King Dalios is troubled by the disappearance of Krasis and the threat to the Kronos crystal, which is guarded by the Minotaur at the heart of a maze. The Master has travelled to Atlantis in search of the crystal and soon inveigles himself at court, wooing Queen Galleia. When the Doctor and Jo arrive, the unnaturally long-lived King confides that Atlantis turned from Kronos and sought to end the link by which the chronovore could be controlled, by destroying the crystal, but they could only splinter it. The Doctor then faces the Minotaur to rescue Jo, duped into the maze by Krasis, and the creature is destroyed. The crystal is now produced from the maze – but the Master’s schemes have borne fruit and he has usurped the throne. Jo and the Doctor are soon detained and witness Dalios' death after being smitten with a trident.
Krasis uses the crystal to summon Kronos to Atlantis once more. The enraged chronovore begins to destroy Atlantis while the Master flees in his TARDIS, with Jo Grant in tow. The Doctor heads off in his own TARDIS in pursuit while Kronos destroys the city and people of Atlantis. In the vortex, the Doctor threatens the mutually assured destruction of both TARDISes by a "time ram" in which both vehicles would occupy the same space/time co-ordinates. When he carries this threat out, a thankful Kronos is set free, saving the Doctor and Jo and returning them to their TARDIS. On the Doctor’s insistence, the Master is spared, too, but he flees in his own TARDIS before he can be apprehended. The Doctor and Jo return to the institute, where normality is returning, through a final use of the Master's machine, which now overloads, and the time experiments end.
Production
According to the comprehensive production documentation released in 2023 as part of the 'Season 9 Blu Ray Collection', when Sloman was commissioned to write the final six part story for the season in May 1971, it was titled "The Daleks in London". By December 1971, the idea had been abandoned and Sloman's contract was amended to write "The Time Monster". [1]
This story sees a redesign of the TARDIS interior. [2] Producer Barry Letts was unhappy with the redesign. The set was damaged shortly after recording on this particular serial wrapped and, as a result, was discarded.
Although the PAL mastertapes had been wiped, NTSC copies were returned to the BBC from TVOntario in Canada in 1983. In 1987, a low band 625-line monochrome tape of Episode Six was discovered at the BBC. It was recoloured by combining the black-and-white picture with the 525-line colour signal of the episode, creating a superior copy to the NTSC one.
