Dawn broke over London as Richard Blade's train pulled into the station. It was a dawn that promised a clear, sunny day, rare for London at this time of the year. It was a pity, thought Blade, that he'd been spending the morning sleeping and the afternoon far below the Tower of London. By the time sunset flamed over London, he would be far away from the city, from Britain, from the whole world.

He would be somewhere in Dimension X, the infinite unknown on the other side of a barrier made by his own brain and his own senses. When that brain was linked to Lord Leighton's computer, when those senses were twisted out of their normal shape, the barrier vanished.

He'd crossed into Dimension X twenty-seven times since the day Lord Leighton first linked his brain to a computer and opened the door to Dimension X. Each journey brought new dangers to test Blade's skill and strength to the limit. He'd escaped from some of those dangers by the narrowest of margins. Sooner or later, he would not escape at all, unless someone else could be found-someone able to travel into Dimension X and return to Britain alive and sane. For the time being, that someone did not exist. Richard Blade was the only living human being who could cross from Home Dimension into Dimension X and return without destroying his mind or his body.

Yet whatever the danger to him, he could not end his travels into Dimension X. Out there lay resources and knowledge beyond price. The exploration of Dimension X had to continue, whatever the risk to Blade, whatever the frustrations when a possible discovery turned out to be nothing, whatever their ignorance of the dangers. It had to continue, in the hope that Project Dimension X would someday justify all the blood, sweat, knowledge, and money that had been poured into it since it began. The stakes were too great.