It's the year 5000, the year of the Great Breakout. The Doctor is fighting for his mind in this story. After answering a mayday from Titan Base, inbetween Jupiter and Saturn, the Doctor comes across some personnel who are infected with a virus. One can tell due to the fuzzy gray and white around their eyes and forehead, and the mechanical voice they speak. Whenever someone is infected, that person utters, "Contact has been made!" The Doctor too is infected... but not Leela. Why not me, she wonders? Is it due to her being all instinct and intuition? Indeed, her sensing something evil in the beginning of the story is true to her hunting instincts. That's nothing compared to the fact that due to the Doctor's intelligence, his mind is ideal serving as the host of the Nucleus of the virus.
The Doctor and Leela go to the Center for Alien Biomorphology on Asteroid K067, where the former undergoes treatment by the station head, Professor Marius, who happens to have a robot dog named K9, a personal database as well as a good friend.
The highlight of this story is where miniaturized clones of the Doctor and Leela are injected into the Doctor's brain, which is a very colourful impressive set. "I've never been in anybody's head before," says Leela 2. They encounter phagocytes, passing thoughts, and electrochemical signals. However, as many viewers have pointed out, the clones should've been naked instead of being reproduced with clothes.
This is the debut story of K9 Mark I, the robot dog that accompanies the Doctor up to The Invasion Of Time, before his twin K9 Mark II, picks up for another two seasons. His offensive nose photon gun is put to good effect. However, in the scene where he shoots a part of a wall as a defensive barrier, one can clearly see the pieces has been precut. And the old white control room is seen once again for the first time since Pyramids Of Mars (1975).
An interesting piece of Earth history has been developed in the Who mythos. The Great Breakout is where humans are colonizing asteroids. "The asteroid belts are teeming with them. New frontiersmen, pioneers, waiting to spread across the galaxy like a tidal wave, or a disease." When Leela protests, he kindly explains that he likes humans, "but when they get together, other lifeforms sometimes suffer." The theme is later pursued when the Nucleus tells the Doctor of its purpose and justification for its existence: "the rught to survive, multiply, perpetuate. We are all predators, Doctor. We kill, we devour, to live... survival is all, you agree?"
One interesting observation is the English used on the Bi-Al Foundation. It's clearly a phonetic kind, e.g. Isolayshun Ward, Shutle Entry, Egsit... Oh dear, how the human race has fallen!
Michael Sheard (Lowe) not only appeared in four other Who's--The Mind Of Evil (1971), Pyramids Of Mars (1975), Castrovalva (1982), and Remembrance Of The Daleks (1988), but is best known as Admiral Ozzel in The Empire Strikes Back. And Kenneth Waller (Hedges), briefly seen, is best known as Old Mr. Grace in the 1981 season of Are You Being Served?
The second story of Season 14 is a good one overall, with some great spaceship models and the base on the Titan moon, and of course the asteroid.