Franklin Roeder, head of Roeder Agrochemicals Ltd., has developed a killer pesticide spray by applying the principle of weedkiller (that the weeds outgrow themselves and die) to insects. The first part is a huge success; everything from frogs to wood lice become bloated under its effects; but the second part is much more of a problem; most of the creatures stubbornly refuse to die. Roeder persuades his lab scientists to lie in their reports, so as to get an early release date for his pesticide. Meanwhile the effects of the spray are causing a plague of oversized and hungry insects.