Were the two dimensions completely parallel. . with only the state of Blade's brain and therefore of his senses standing between them? Or were they merely parallel in some ways and divergent in others, each with some sort of independent continuity? Since their times could get out of phase, Blade suspected the latter. Lord Leighton also suspected the latter and had nearly had kittens about it more than once. However, he had also adjusted the computer so that Dimension X time and Home Dimension time stayed in phase.

In fact, Project Dimension X was developing all sorts of complications that not even Lord Leighton had anticipated the first time he plugged Blade's brain into what now seemed like a primitive and remote ancestor of the computer around which the project centered. There was a search for other suitable men who could survive the trip into Dimension X. . a search so far unsuccessful, although J was making discreet inquiries of American intelligence agencies, the prime minister himself, the British intelligence services, and the armed forces. The stresses of passing into Dimension X were enormous, and once there, a man also had to have the wits, reflexes, and muscles to cope with an environment that might threaten him with anything from Stone Age ape-men to nonhumans from interstellar space.

One other man had passed into Dimension X, to be sure, and had even survived there-until he encountered Blade. But that one man had been Blade's Russian Doppelganger, a carefully trained and carefully chosen twin of Blade himself, created by the KGB. Now he lay dead in Sarma. Finding another twin for Blade among the ranks of the free world's trained soldiers and agents was improbable-and creating one was unacceptable. They would just have to keep on searching and hope for good luck.

There was also a project for finding a way of repeating trips into one dimension, so that it could be explored thoroughly.