Adam is an old man, aware of the decay of his body and of all the bodies around him. He also believes that the body and the soul are not two ways of describing the same thing, namely a human being, but distinct, separate entities. One night, at a party, he is told of a London clinic that is pioneering a new, expensive technique transplanting an individual's brain - and thus his essence - into a younger, fitter body of his choice (of course, this is very bad science, but a good fictional set-up).