 Professor Bob Mandle, a young scientist, dies mysteriously while discussing the rocket failures with Armstrong.Armstrong learns that the only remaining authorities of comparable stature are Professor Claire Mandle, the dead man's sister, and a Viennese scientist named Horowitz.Armstrong visits New Mexico, where the eighteenth Moon-rocket, to be piloted by George Quinn, is being built under the supervision of the obstructive Ambrose Fothergill.