An explorer discovers that native African wood carvings are actually an advance fifth column invasion force under the command of Moomba. Moomba gives his command to strike and all the carvings get up and begin to herd and intimidate their human owners as the wood they are crafted of is so dense that neither fire nor any other human weapons can defeat them. Using unknown means, a native African witch doctor defeats Moomba and extracts a promise from him to leave Earth along with all of his warriors.; A strident anti-robot activist is convinced of the worth of robots when his son is saved by his robotic playmate.; The space pilot landing on an asteroid is perplexed by a voice from nowhere pleading for help, but he realizes that the asteroid itself is the source of the voice.