From the back:
To a society dependant on robots, the news that these benign, tireless, obedient labourers could be turned into killers would cause panic. So it was kept a secret. In Kaldor City, only the three survivors fo the Sandminer massacre know the truth. But now, several years later, they are beginning to show signs of mental breakdown. And once again, the robots are being programmed to kill. Can the dead genius Taren Capel possibly be involed in this new outrage?
Worst of all, this time the deadly robots are not confined to a Sandminer. This time they are loose in Kaldor City. And this time, unless the Doctor and Leela can stop them, they really will destroy the world...
Featuring the Fourth Doctor and Leela, this adventure takes place between the BBC Doctor Who novel LAST MAN RUNNING and the TV story THE TALONS OF WENG-CHIANG