"I fear it cannot be done. That part of the city is strictly forbidden. Vaajo's palace is there, and the homes of his scientists, all surrounded by the wall. Even the few servants who are permitted to pass in and out occasionally are painstakingly examined." "I've got to get in there," Ketrik reiterated. "And I intend to!" "Wish I could help you. It might be for the best! Dar Vaajo is becoming as hated as he is feared, yes even by his own people! Something monstrous and mad is going on in those laboratories!" "What can you tell me about it?" Thurlo's eyes became dark, and his voice lowered. "Only this: Frequently, in the dark of night, a faint greenish glow comes over the city. It only lasts a few seconds, then withdraws into a pillar of concentrated fire _directly over the laboratories_! Then it seems to extend itself, lashing outward into space." "Greenish fire!" Ketrik exclaimed. "Do you mean electronic power, Thurlo?" "No, not that at all. I'm no scientist, but I know this is _cold light_. It's different--devilish! You may laugh at me, Ketrik, but I will say it. These radiations seem alien to this world, to this universe; they seem almost--_alive_!" But Ketrik did not laugh. He was remembering the mad survivor of a missing Earth spacer. He was remembering the poor gibbering devil he had seen but recently in the tunnel. He thought of these and other things, and felt the hair at the back of his neck begin to rise. "Why," Thurlo was grumbling, "did Vaajo have to come _here_ to conduct his devilish experiments? Why could he not have stayed in the northern capital?" "Because here he is in close contact with the Rajecs," Ketrik said experimentally, and watched for the little Martian's reaction. "Yes!" Thurlo nodded. "I can tell you something about that, too. Under the treaty, the Rajecs are allowed access to Turibek or, if they wish, other cities to the north. Vaajo has even built a magnificent temple here, where they can carry on their own ritualistic worship. Well--I've seen those black caravans come into the city, quite a number of them in the past weeks. But one sees little of them afterwards! Of course they may be shunted further north...." "No!" Ketrik smacked a fist into his palm. "No, Thurlo, for some reason they are needed here! It's all a part of Vaajo's plan--I knew it!" "I care little about the Rajecs," Thurlo shrugged. "It is well that they disappear." Ketrik thought differently. He lay awake in the little cubicle to which Thurlo assigned him, his mind too turbulent for sleep. The pattern, though still vague, was beginning to take shape. At least he had gained entrance to Turibek! Tomorrow he would make a short tour about the city, try to formulate a plan. At last his tired muscles relaxed, and he dropped into an untroubled sleep. * * * * *