Kinnison had said that there was no possibility of tracing a hyperspatial tube after it had ceased to exist. There were millions of planets in the two galaxies. There was an indefinite, quite possibly an infinite number of coexistent parallel spaces, into any one of which the tube might have led. Knowing these things, Kinnison had decided that the probability was infinitesimally small that any successful investigation could be made along those lines. Tregonsee and Camilla, starting with the same facts, arrived at entirely different results. There were many spaces, true, but the inhabitants of any one space belonged to that space and would not be interested in the conquest or the permanent taking over of any other. Foreign spaces, then, need not be considered. Civilization had only one significant enemy: Boskonia. Boskonia, then, captained possibly by Kandron of Onlo, was the attacker. The tube itself could not be traced and there were millions of planets, yes, but those facts were not pertinent. Why not? Because "X," who might or might not be Kandron, was not operating from a fixed headquarters, receiving reports from subordinates who did the work. A rigid philosophical analysis, of which few other minds would have been capable, showed that "X" was doing the work himself, and was moving from solar system to solar system to do it. Those mass psychoses in which entire garrisons went mad all at once, those mass hysterias in which vast groups of civilians went reasonably out of control, could not have been brought about by any ordinary mind. Of all Civilization, only Nadreck of Palain VII had the requisite ability; was it reasonable to suppose that Boskonia had many such minds? No. "X" was either singular or a small integer. Which? Could they decide the point? With some additional data, they could. Their linked minds went _en rapport_ with Worsel, with Nadreck, with Kinnison, and with the principal statistician at Prime Base. In addition to Nadreck's locus, they determined two more--one of all inimical manifestations, the other of those which Nadreck had not used in his computations. Their final exhaustive analysis showed that there were at least two, and very probably only two, prime intelligences directing those Boskonian activities. They made no attempt to identify either of them. They communicated to Nadreck their results and their conclusions. "I am working on Kandron," the Palainian replied, flatly. "I made no assumptions as to whether or not there were other prime movers at work, since the point has no bearing. Your information is very interesting, and may perhaps prove valuable, and I thank you for it--but my present assignment is to find and to kill Kandron of Onlo." * * * * *