In spite of the Prime Minister's generosity with priorities, financing, and staffing, Project Dimension X still had a weak point. That weak point was Richard Blade himself. J grinned wryly at the notion of Blade, with his mind and body and experience, being a «weak point.» Then the grin faded.

It was true. Dimension X could not be explored or exploited without somebody going through the computer. So far, the only person able to go through the computer and return alive and sane was Blade himself. One other man had tried; he had returned permanently insane. A dozen others had been considered; all had been rejected. All fell short of Blade's perfection.

But however perfect Blade might be, there was a limit to what he could take. Sooner or later his brain would suffer major damage from too much stress placed on it too often by the computer. Even worse, somewhere out in Dimension X his mighty strength might not be great enough, his lightning reflexes not fast enough, and he would not come back at all.

It was absolutely necessary to find at least one other man, and preferably several, who could survive a trip into Dimension X, both physically and mentally. They needed to take the strain off Blade for his sake. Even more, if he cracked or vanished before they found somebody else, the whole Dimension X project would come to a standstill, possibly for good. That would benefit nobody and nothing.

All of which explained why J was in the official Rolls-Royce heading into London. An hour ago he had been high over the Atlantic in an airliner. To all eyes he had been a tall, elderly impeccably Establishment businessman or civil servant. He had just completed a mission to Washington, a mission personally ordered by the Prime Minister. He had been discreetly inquiring of the Americans whether they had any good agents that might be available for a joint Anglo-American project.