In shape the thing did somewhat suggest a flame, but such a flame as never seen before. It was a writhing mozaic of colors that twined and faded one into the other. It curled as he watched, and the gleaming tip bowed slowly until it touched the floor. The thing lay flat, pulsing slowly with a gorgeous display of color. Cargyle forgot the mutineers, the beleagured officers. In sheer bewilderment he watched the deliberate, enigmatic movements of the thing before him. In all his wandering through the system he had never seen anything like this. What was it? A phenomenon of space, heretofore unknown, or was it--alive? The tip of the thing, bent to the floor, was moving delicately in small circles, touching and retreating, almost in the manner of a caterpillar on a leaf. Cargyle was crouched on one knee. Abruptly his foot slipped, the heel coming down hard on the metal floor. The resultant clangor in that narrow tube was deafening. The flame-like entity sprang vibrantly erect. A huge red bubble, swelling, emerged from somewhere within its body and wound upward through vellicating strands of color. The thing paused there, its inner wonder of radiant light in flickering, nervous agitation. The tip, aloft again, twisted and writhed, once forming a superb, faultless spiral of brilliant scarlet. * * * * * The next moment it was moving toward him, and Cargyle, who had faced undaunted the thousand dangers, the unearthly foes of the spaceman, found himself shaking with a resistless horror. Furious at himself, he took deliberate aim, and fired. If the slip of his foot had been thunderous, the sound that followed the discharge of the blastor pistol was as that of worlds coming together. The walls of the passage shivered to the detonation, so terrific that an entrance door to the passage burst from its hinges, and fell into the cabin on which it opened. Deafened, and blinded by the sudden flash, Cargyle waited helplessly. When his vision cleared he stared eagerly down the corridor. The flame-thing was where he had seen it last, motionless, unharmed! As he stared in astonishment a roll of emerald smoke seemed to eddy under its surface, and it moved toward him. A recurrent wave of that strange horror surged through Cargyle. What _was_ this thing? Was it sentient--did it perceive and threaten him? He thrust his pistol back in his belt--apparently it was useless against whatever stood before him--and started grimly forward. The thing waited, pale colors flowing fluidly through it. Suddenly it seemed to thin and tower and in its middle a ring appeared--a ring of dead black--and from that ring burst a blast of light; an intolerable, blinding beam that flamed in the very core of Cargyle's brain. Agony seared through him, rose to a piercing crescendo. Then a merciful blackness engulfed him, and the second officer crumpled to the floor. The flame-thing took up its incessant tapping and probing.