In the far future, the material needs of humankind are tended by the omnipresent Machine, which makes their environment, in vast tunnels beneath the earth, comfortable and safe. But safe from what? And what if the Machine Stops? A young boy, Kuno, finds his questions can't be answered until he has lifted the veil of security and trespassed upon the surface.

A stranger calls at the home of divorcée Anna Preston, asking to collect some of her ex-husband's belongings. Anna agrees, but is suspicious, and tries to contact her 'ex' at the space-research establishment where he worked. But none of his colleagues can tell her where he is and the authorities block all her efforts to find out. Anna grows more convinced that he is in danger, but the truth is more horrifying than even she can imagine.

Why take the Great Circle route to Australia when you can tunnel through the very molecules of the solid earth itself in a TAU-mode shuttle? When a routine TAU-shuttle becomes entombed in solid rock miles under the earth, the only means of rescue may be the wildly experimental LAMBDA-mode shuttle; and even its creator has no idea how it will behave, or whether its pilot can keep his sanity during the rescue mission.

In the huge, labyrinthine nuclear bunker meant to shield the survivors in government from the aftermath of atomic war, Level 7 is the deepest and the safest from radiation. But in spite of its hermetic isolation, the nerve center of government is ultimately not safe from the consequences of the holocaust which rages miles overhead.

Charles Dennistoun, a 60-year-old contestant on 'You Bet a Million' - a quiz show for millionaires - wins the jackpot prize, a course in rejuvenation. But his friends and family have mixed feeling, and the repercussions have blackly comic effects on all concerned.

College student Sarah Richards is alone in fearing and disliking the new teaching machines but even she does not foresee the terrifying situation that arises when her supervisor, Stephen Kershaw, re-arranges the machines to conform with revised fire regulations.

Déja vu: as Guy Birkett goes through the day he has a nagging feeling that he's been here before, experienced this already; except the details are always different. Is it conceivable that he is merely a simulacrum, the ultimate in consumer market surveying? He finds there is a reality behind the reality he knows; but for a pawn to question the reality of the chessboard is a perilous undertaking.

Amos Handworthy's grandfather was quick on the draw: as a U.S marshal it was a job requirement if you wanted to stay alive. But now Amos has built a gun-slinging robot, programmed to be a split second slower than him in a gunfight, so that he can perpetuate the myth and glory of his grandfather's frontier past. But will Amos bet his life on a duel with real bullets?

Dr Andrew Cook, inventor of a process for making living replicas of human beings, has unwittingly duplicated himself and becomes a secret weapon in the Solar System's struggle for economic survival against a powerful alien culture, the Sentients.

Dr Saint's offer of a free place in his comfortable old-folks' home appears entirely philanthropic to Miss Claythorpe. However he is suspiciously vague about the treatment that goes with it.

A human-looking robot housekeeper is the latest gadget to acquire in the ceaseless battle to keep up with the Joneses. But housewife Claire Belmont starts to question the wisdom of her husband's purchase when TN3 (Tony) arrives. Can a man-like robot do everything a man can do: but willingly, obediently, tirelessly? Is a robot less than a man, or more?

Robot QT-1, aboard an orbiting space-station, controls the massive energy beam which transmits the sun's power to receivers on Earth. But QT-1 (Cutie) has some strange bees in his positronic bonnet. How could weak creatures of protoplasm create a nearly invincible, totally logical entity like himself? It is up to his human supervisors, Powell and Donovan, to convince Cutie of his niche in creation before his new robot theology becomes a threat to all life on Earth.