Eleven different ones so far, but the number was doubtless nearly infinite. With Lord Leighton's computer linked to the man's brain, he would vanish from beneath the Tower-from Home Dimension. He would awaken-somewhere else-in Dimension X, always naked, usually with a splitting headache; and more often than not with a great need to both think and act fast to stay alive. The dimensions varied widely, and most of them sounded like a madman's ravings when put down on paper. But they all seemed to have one thing in common-they were all filled with deadly dangers.

The project revolved around four key men. Lord Leighton had developed the computer-a monster two or three generations beyond anything else believed possible in the rest of the world. The Prime Minister provided the money that the project gobbled up by the hundreds of thousands of pounds, and fought off indiscreet questions from curious M.P.s. J acted as liaison and field man for both the scientist and the politician, since he had more freedom of movement than either. And as head of the secret intelligence agency MI6, he had provided the fourth key man.

Richard Blade. Recruited by MI6 while still at Oxford, he had fulfilled his early promise ten times over. He had been MI6's best agent for the better part of twenty years, expert in both the thinking and the rough-and-tumble ends of the business. He had been the secret of many of the agency's most successful operations. He had, in fact, become virtually indispensable. J would have esteemed him highly even if Richard had not been so much like the son he had wanted.

But those same exceptional qualities of mind and body that had made Richard Blade a superlative field agent had also made him the perfect man to travel into Dimension X. Or perhaps not perfect, but so far the only man in the Free World able to travel into Dimension X and return alive and sane. He was able to explore those Dimensions and bring back their science and technology to aid England. And more often than not, he managed to help the people in each Dimension cope with problems of their own. Richard was a natural leader. Set him down in the middle of a wilderness full of howling savages, and in a few months his wits and his muscles would have enabled him to rise to power. That had happened more than once out in Dimension X.