The day-dream of being marooned on a desert island still has enormous appeal, however small our chances of actually finding ourselves stranded on a coral atoll in the pacific. But _Robinson Crusoe__ was one of the first books we read as children, and the fantasy endures. There are all the fascinating problems of survival, and the task of setting up, as Crusoe did, a working replica of bourgeois society and its ample comforts. This is the desert island as adventure holiday. With a supplies-filled wreck lying conveniently on the nearest reef like a neighbourhood cash and carry.

More seriously, there is the challenge of returning to our more primitive natures, stripped of the self-respect and the mental support systems with which civilisation has equipped us. Can we overcome fear, hunger, isolation, and find the courage and cunning to defeat anything that the elements can throw at us?

At an even deeper level there is the need to dominate the island, and transform its anonymous terrain into an extension of our minds. The mysterious peak veiled by cloud, the deceptively calm lagoon, the rotting mangroves and the secret spring of pure water together become out-stations of the psyche, as they must have done for our primeval forbears, filled with lures and pitfalls of every kind.

The Pacific atoll may not be available, but there are other islands far nearer to home, some of them only a few steps from the pavements we tread every day. They are surrounded, not by sea, but by concrete, ringed by chain-mail fences and walled off by bomb-proof glass. All city-dwellers know the constant subliminal fear of being marooned by a power failure in the tunnels of a subway system, or trapped over a holiday weekend inside a stalled elevator on the upper floors of a deserted office building.

As we drive across a motorway intersection, through the elaborately signalled landscape that seems to anticipate every possible hazard, we glimpse triangles of waste ground screened off by a steep embankments. What would happen if, by some freak mischance, we suffered a blow-out and plunged over the guard-rail onto a forgotten island of rubble and weeds, out of sight of the surveillance cameras?

Lying with a broken leg beside our overturned car, how will we survive until rescue comes? But what if rescue never comes? How do we attract attention, signal to the distant passengers speeding in their coaches towards London Airport? How, when faced with the task, do we set fire to our car?

But as well as the many physical difficulties facing us there are the psychological ones. How resolute are we, and how far can we trust ourselves and our own motives? Perhaps, secretly, we hoped to be marooned, to escape our families, lovers and responsibilities. Modern technology, as I tried to show in _Crash__ and _High Rise__, offers an endless field-day to any deviant strains in our personalities. Marooned in an office block or on a traffic island, we can tyrannise ourselves, test our strengths and weaknesses, perhaps come to terms with aspects of our characters to which we have always closed our eyes.

And if we find that we are not alone on the island, the scene is then set for an encounter of an interesting but especially dangerous kind…