Parts: 6
Writers: Robert Sloman, Barry Letts
Airdates: 20 May 1972 - 24 June 1972
Production Code: OOO
Megalomaniac of the Week: the Master
Creature Feature: Kronos
Special Guests: UNIT (the Brigadier, Benton, Yates)
Story: A disturbing dream featuring the Master, a glowing crystal and an eruption has the Doctor on edge. Aware that the Master could be plotting something that will put the world in peril, he puts UNIT on alert while he and Jo begin researching the elements of his dream to see if they correlate with anything in the real world. Jo recalls reading about an eruption off the Greek coast, in an island chain where Atlantis was said to have existed.
Meanwhile, at a nearby university, the Master - posing as a professor - is overseeing a project called TOMTIT, or Transmission Of Matter Through Interstitial Time. The team working on TOMTIT are aware that it will have the ability to instantly transport matter from one place to another, but the Master has not told them about the other purposes to which it can be turned. When the Brigadier and Benton arrive to witness a trial run, the machine refuses to shut off...and by the time they correct the error, one member of the team has been aged sixty years.
The Master is toying with time in a very dangerous way - he intends to summon into our reality a creature from outside the very fabric of the space-time continuum...a creature that eats time itself. To stop him, the Doctor and Jo will have to travel back to the lost city of Atlantis and confront the high priest of the god Kronos, a mythical beast with killer instincts...and the Chronovore. If they want to save the universe from its voracious hunger for destruction, the Doctor and Jo must be prepared to sacrifice their lives.