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7. THE FOSTERS
Bio-chemist Dr. Harold Gerwyn is puzzled by a man on the 'phone warning him that his wife will fall ill. He is deeply shaken when she indeed does, going into a mysterious coma for which the hospital is unable to find either cause or cure.
The man 'phones again, instructing Gerwyn to go to an address. He arrives to find Mr. Foster and his sister awaiting him in the front garden - to all appearances a charming old couple living out their lives in sleepy suburbia.
But these appearances prove increasingly false as the Fosters lead Gerwyn into their house. Calmly they explain they have infected his wife with a unique steroid enzyme that will sustain the coma until an antidote is applied. If Gerwyn refuse to co-operate, she will surely die.
Co-operate in what way? If he'll just step into this back-room, they'll show him the Subject .... This, lying amongst a mass of complex equipment, turns out to be Geoff Hirst, a young man whom the Fosters have rendered similarly comatose. Now, if Gerwyn will just arrange for the loan of an artificial metaboliser from the lab where he works ....
To his horror, Gerwyn realises they plan to operate, in vivo, on the boy's brain .... Though with what aim the Fosters as yet refuse to reveal. "You'll be murderers," he says. "Oh, we've been that for a very long time," they retort. However, they convince him also of their superior powers, to suggest a solution to a hitherto insoluble problem in his research work.
It's crazy - impossible! This doddery old couple, dreaming up an inspired solution which, when he checks it at the lab, actually works! Even crazier when Gerwyn's daughter Sally establishes that Foster is a retired stockbroker with a blameless past.
Reluctantly Gerwyn realises that, whoever they may have been, the bodies of the Fosters are now possessed by beings of a vastly superior intellect. Beings, moreover, with macabre designs on the living brain of a boy; and beings whom, for the sake of his wife, he must agree to help.
As he goes off with the metaboliser to do just that, Sally is left to follow their one possible lead: the origins of the boy Geoff. She dare not risk going to the police. She knows she has but a few hours before her father becomes a party to murder.
And what, Gerwyn asks the Fosters, is the mysterious secret they seek locked in the human body? The will, they answer, staring with contempt at the boy's body - the simple will to live. That instinctive urge which, in their more highly evolved society, has dwindled to such an extent that now their whole existence is threatened.
Written by Michael Ashe