The ultimate fantasy? Or a nightmare of self-discovery? From the renowned author of 253 comes a dark, erotic fable for the modern age. David, a young scientist investigating what happens to the brain during the process of learning, suddenly finds himself the subject of a bizarre experiment. On the way home from the lab one night he spies Tony, a fitness instructor from his gym, on the same platform waiting for the tube. David's had an obsession with Tony for weeks, but David is no Adonis and Tony's barely noticed him at all. Until now. When David imagines Tony naked, a pleasant fantasy to spice up a dull journey home, an extraordinary thing happens: Tony strips there and then on the platform and offers himself in front of all onlookers. Horrified, David flees. But back at his flat, Tony reappears, as if by magic. And disappears, when David wishes him away. And reappears when he calls him back. Being a scientist, David recognises an experiment when he sees one, and sets out to test hypotheses. In quick succession he conjures up Billie Holliday, Johnny Weismuller, Daffy Duck, Picasso, Sophia Loren, even his younger self. Mad with lust and losing all scientific objectivity, he runs the gamut of his fantasies until, sated and morally bankrupt, he's forced to confront himself. He realises he is the subject of a divine experiment into human temptation, free will and the excercise of power.